Michel Boeckstyns - Academia.edu (original) (raw)

Papers by Michel Boeckstyns

The Journal of Hand Surgery, 1984

A retrospective study of the results after surgical treatment of scaphoid nonunion in two orthope... more A retrospective study of the results after surgical treatment of scaphoid nonunion in two orthopedic centers is described. One center used Bentzon 's soft tissue-arthroplasty method in 15 cases, and the other center used Matti - Russe bone grafting procedure in 32 cases. Of these 47 cases, 46 had established pseudarthroses. The clinical results were similar in both methods (average follow-up time: 61.4 and 44.0 months, respectively). Soft tissue arthroplasty permitted an earlier return to work, but the risk of long-term degenerative changes developing cannot yet be excluded.

The Journal of Hand Surgery, 1985

Twenty-six patients with scaphoid nonunion were reexamined 22 to 39 years after Bentzon's... more Twenty-six patients with scaphoid nonunion were reexamined 22 to 39 years after Bentzon's soft tissue interposition arthroplasty was performed. All but one were satisfied, although three still had moderate pain. Mobility of the wrist was reduced by 20% to 25% and grip strength by 8%. The nonunion remained open and unstable in 16 of 25 radiologically reexamined cases. Carpal collapse, which had increased over time, was found in 15 cases, nine of which presented an unstable nonunion. Osteoarthritis had developed in five of 15 wrists with carpal collapse and in two of 10 without it. No significant osteoarthritis was found in any case earlier than 27 years after the operation. Thus, the risk of disability that is due to late degenerative changes of the wrist is small, even in the presence of carpal collapse.

Pain, 1989

Ninety-two knees in 46 patients were evaluated with regard to pain: in 51 of these knees, implant... more Ninety-two knees in 46 patients were evaluated with regard to pain: in 51 of these knees, implantation of a hinged endoprosthesis had been performed. The reliability and validity of 2 pain evaluation methods were assessed: the knee-pain questionnaire method (standard version including 10 questions and modified version including 14 questions) and the visual analogue scale method (standard version without numbering and O-10 scale). The visual analogue scale-standard version and O-10 scaleturned out to be more reliable than the questionnaires. The O-10 scale was the most valid when compared to the patients' own opinions regarding pain.

Danish medical journal, 2014

Treatment of base fractures in the proximal phalanx depends on the fracture type, the degree of d... more Treatment of base fractures in the proximal phalanx depends on the fracture type, the degree of displacement and whether fracture reduction is stable or not. Internal fixation often leads to decreased mobility of the injured finger despite exact reduction of the fracture. Our treatment is focused upon function and to a lesser extent on exact reposition of the fractured fifth digit. Buddy taping was used after initial, closed reduction of the fracture allowing for immediate mobilisation. This was a prospective follow-up study of 53 consecutive conservatively managed base fractures in 53 patients with a mean age of 39 years. All fractures were treated with buddy taping to the fourth digit and immediate mobilisation. The subjective outcome showed high overall satisfaction, and only four patients reported mild pain at rest or work. Malrotation was noted in three cases, none of which needed corrective surgery. All but one patient regained full flexion of the affected finger. Satisfactory...

Journal of Hand Surgery (European Volume)

evidence to support that surgery indeed speeds up recovery in all such patients because of the ra... more evidence to support that surgery indeed speeds up recovery in all such patients because of the rarity of this disorder. I agree with the approach taken by David Elliot; conservative treatment for at least 6 months and not rushing to surgery for these patients. Nowadays, some patients may not tolerate waiting for 6 months. The willingness to go through a lengthy period of conservative treatment, as well as perspectives on cost of surgery vary globally in different subsets of patients. For example, we may encounter situations where the surgeon has advised that the compression usually resolves spontaneously without surgery and the risks of surgery, but the patient still wishes to undergo surgery to achieve a possible faster recovery. Earlier surgery seems acceptable for this subset of patients when the surgeon and the patient have made a joint decision. In these situations, it is key that the patient fully understands the surgery is unnecessary for recovery and also that the surgeon had not presented surgery as a necessary or the only solution. My recommendation would be that any surgeon who encounter a case of AIN compression consider neuritis the initial diagnosis. It is entirely possible that compression of the nerve by the normal surrounding tissues simply does not exist and that nearly all or all of these patients may, in fact, have neuritis. If symptoms persist for months, surgeons should investigate for any space-occupying disorders around or in the AIN or any constriction inside the AIN with MRI or ultrasound examination. When ultrasound is available in the clinic, the nerve is best examined with ultrasound in the initial clinic visit. Finally, it is important to note that compression of the AIN, as discussed above, differs slightly from the scope of AIN syndrome (Figure 2). The latter is broader and can be caused by pathologies of the AIN (Figure 2). The disorder of pathologies occurring within the nerve does exist as reported (Pan et al., 2014), and is not caused by external compression. This letter compliments my earlier article about median nerve compression (Tang, 2021), in which I discussed FDS-pronator syndrome and lacertus syndrome. That article, however, did not include any detailed discussion of AIN compression as it is rarer, and I suspect that most or all of the patients with spontaneous recovery of AIN compression, as seen by other surgeons, might have had neuritis. Entrapment neuropathy of AIN – namely, compression by the surrounding tissues – may exist only rarely or not at all.

Journal of wrist surgery, 2020

Purpose Various implants have been described for ulnar head replacement (UHR) or for total repla... more Purpose Various implants have been described for ulnar head replacement (UHR) or for total replacement of the distal radioulnar joint (DRUJ). Many series are small and few reports on mid- or long-term results. This study is primarily aimed to report on the midterm results after ulnar head only and total DRUJ replacement using the uHead in the treatment of painful disorders of the DRUJ. The secondary aim of the study was to eventually assess the combination of UHR and total wrist arthroplasty (TWA). Materials and Methods We included 20 consecutive patients in whom an UHR with the uHead was performed at our institution between February 2005 and March 2017. There were 6 men and 14 women with mean age of 59 years (range: 36-80 years). The mean follow-up time was 5 years (range: 2-15 years). Data were recorded prospectively before operation and at follow-up examinations and entered in a registry. The patients were followed-up at 3 and 6 weeks and 3, 6, and 12 months postoperatively and...

Hand Clinics, 2017

Wrist arthroplasty provides functional mobility, improved strength and upper limb function, and r... more Wrist arthroplasty provides functional mobility, improved strength and upper limb function, and reduced pain in carefully selected cases of severely destroyed wrist joints. Indications are severe wrist destruction due to rheumatoid arthritis (RA), idiopathic osteoarthritis (OA), scapholunate advanced collapse (SLAC) wrist, malunited intra-articular distal radius fractures, acute irreparable distal radius fractures in the elderly, and Kienbö ck disease. High physical demand, young age, poor bone stock, and spontaneously fused wrist in patients with RA are generally contraindications. Implant survival rates have improved with the latest designs but do not compare with the survival rates of hip and knee arthroplasties.

Journal of Hand Surgery (European Volume), 2019

Annals of Neurology, 2017

Objective: Sensation is essential for recovery after peripheral nerve injury. However, the relati... more Objective: Sensation is essential for recovery after peripheral nerve injury. However, the relationship between sensory modalities and function of regenerated fibers is uncertain. We have investigated the relationships between touch threshold, tactile gnosis and mechanoreceptor and sensory fiber function after nerve regeneration. Methods: Twenty-one median or ulnar nerve lesions were repaired by a collagen nerve conduit or direct suture. Quantitative sensory hand function and sensory conduction studies by near-nerve technique including tactile stimulation of mechanoreceptors were followed for 2 years, and results were compared to non-injured hands. Results: At both repair methods, touch thresholds at the finger tips recovered to 81±3% and tactile gnosis only to 20±4% (P<0.001) of control. The sensory action potentials (SNAPs) remained dispersed and areas recovered to 23±2% and the amplitudes only to 7±1% (P<0.001). The areas of SNAPs after tactile stimulation recovered to 61±11% and remained slowed. Touch sensation correlated with SNAP areas (P<0.005) and was negatively related to the prolongation of tactile latencies (P<0.01); tactile gnosis was not related to electrophysiological parameters. Interpretation: The recovered function of regenerated peripheral nerve fibers and reinnervated mechanoreceptors may differentially influence recovery of sensory modalities. Touch was affected by the number and function of regenerated fibers and mechanoreceptors. In contrast, tactile gnosis depends on the input and plasticity of the CNS, which may explain the absence of a direct relation between electrophysiological parameters and poor recovery. Dispersed maturation of sensory nerve fibers with desynchronized inputs to the CNS also contributes to the poor recovery of tactile gnosis.

Clinical Neurophysiology, 2018

Introduction: The reports on tremor and different types of polyneuropathies have been increasing ... more Introduction: The reports on tremor and different types of polyneuropathies have been increasing and it was suggested to be associated with cerebellar involvement in chronic inflammatory demyelinating polyneuropathy (CIDP). Apart from specific syndromes, the coexistence of polyneuropathy and myoclonus is exceptional. We previously observed cortical myoclonus in cases with inflammatory polyneuropathy who were referred for tremor analysis and aimed to analyze presence of myoclonus and its relation with clinical features in demyelinating polyneuropathies. Methods: We prospectively included all patients with inflammatory polyneuropathy who were admitted between January 2017 and June 2017 and had tremor-like, regular or irregular involuntary movements on clinical examination. All patients underwent neurological examination and multichannel surface electromyography which included upper extremity muscles as well as lower extremity and facial or neck muscles in selected cases. We also recorded long latency reflexes and somatosensory evoked potentials (SEPs) to categorize myoclonus. Results: We identified eight patients with demyelinating polyneuropathy who matched the inclusion criteria: four patients with CIDP, three patients with Guillain-Barre syndrome and one patient with Charcot-Marie-Tooth disease. The mean age was 50.5 ± 19.6 years (range: 26-81 years) and there were seven male patients. Seven out of eight patients had myoclonus, two of which were in the form of polyminimyoclonus. Others had myoclonus on both proximal and distal parts of upper extremities. Negative myoclonus was observed in four of them. Duration of myoclonus was between 30 and 100 ms. only one had duration of 200 ms. Most patients (five out of seven) had cortical myoclonus (with high-amplitude C reflex or SEPs). Conclusion: Myoclonus in the patients with polyneuropathy was irregular tremor-like, however, the electrophysiological characteristics was similar to a cortical subtype. Therefore, it would be interesting to investigate a bigger cohort of inflammatory polyneuropathies for the presence and subtypes of myoclonus and to determine associated clinical features.

Hand Clinics, 2017

Common hand problems are treated differently in different countries. This article attempts to bri... more Common hand problems are treated differently in different countries. This article attempts to bring together the views of surgeons from different countries on some of the most common hand problems that hand surgeons encounter in daily The authors have nothing to disclose.

Scandinavian Journal of Plastic and Reconstructive Surgery and Hand Surgery, 2000

Seventy-six consecutive patients were operated on for advanced Dupuytren's contracture and the re... more Seventy-six consecutive patients were operated on for advanced Dupuytren's contracture and the results evaluated after nine months with special reference to the use of a dynamic extension splint. The patients were separated into three groups: those in whom the splint was used according to our guidelines (n = 15); those in whom the splint was used, but inadequately (n = 15); and those who did not require splinting (n = 24). Our results nine months postoperatively were similar to those of other studies in showing that the fifth proximal interphalangeal joint constituted the greatest problem. Comparison of the three groups indicated that splinting the way we used it did not influence the natural course of the disease after operation.

Chirurgie de la Main, 2015

Introduction Third generation implants for total wrist arthroplasty (TWA) has now been available ... more Introduction Third generation implants for total wrist arthroplasty (TWA) has now been available for more than 17 years. Consequently, an increasing number need revision. Aims of the study To report on our experience with revision surgery after failed TWA. Methods We prospectively and consecutively collected data on all TWA's that were revised in two clinics and made a general follow-up examination in May–June 2015. Findings We revised a total of 19 cases - 8 with rheumatoid arthritis, 11 with other diagnoses. Twelve were revised to a remotion TWA, 1 to an Amandys interposition implant and 6 were fused. At final follow-up, at an average of 31 months after operation, median improvement in QuickDASH score was 25 points, median improvement in VAS score for pain was 50 points. Three revisions TWA had been re-revised and 1 was loose and scheduled for re-revision. There was no difference in QuickDASH- or in VAS score between patients with fusion and patients with TWA. Conclusions Both fusion and revision to a new TWA are feasible after a failed TWA. Revision to a new TWA may require supplementary major procedures.

Neurology, Apr 8, 2014

OBJECTIVE: We investigated reinnervation of muscle fibers and subsequent remodeling of the motor ... more OBJECTIVE: We investigated reinnervation of muscle fibers and subsequent remodeling of the motor unit after complete nerve lesions. EMG was carried out in ulnar or median innervated muscles after nerve-repair by suture or a collagen nerve guide. BACKGROUND: After complete nerve lesions peripheral nerve fibers regenerate. Recovery is dependent of the rate of growth of fibers, the number of axons that regenerate, innervation of target tissue and maturation of regenerated fibers. Recovery is often incomplete, and patients have lasting motor deficits. DESIGN/METHODS: In this randomized multi-center study two procedures for repair of complete nerve lesions were compared. The collagen nerve guide (NeuraGen™) was implanted in 22 of 43 patients and direct suture repair was used in 20 patients and a short graft in 1 patient. The outcome measures included clinical and electrophysiological studies at 1, 3, 6, 12, 18 and 24 months after repair. In a subgroup of 10 nerves repaired by suture and in 11 by nerve guide, quantitative EMG was assessed. A concentric needle was inserted in the muscle at up to 10 sites and the decomposition system EMGtools was used for analysis (IEEE TBE, 2011, 58:2707-2718). We measured denervation; durations, shapes and amplitudes of motor unit potentials (MUPs); and amplitudes and shapes of the recruitment patterns at maximal effort. The parameters were compared with normal controls and the contralateral normal muscle. RESULTS: Denervation activity and absent voluntary activity occurred in all patients at 1 months. MUPs of small amplitude, long duration and polyphasic shape were first recorded after 3-6 months. Denervation gradually decreased and the amplitudes of the MUPs gradually increased while the duration remained unchanged. The amplitude and interference of the recruitment pattern increased. No differences at different repair types were detected. CONCLUSIONS: Regeneration over short gap was supported as well by nerve guide as by suture and in the patient groups muscle reinnervation was similar. Study Supported by: Integra LifeSciences, Corp. Disclosure: Dr. Krarup has received personal compensation for activities with Integra LifeSciences as a speaker, and Abbott Laboratories Inc. as an advisory board member. Dr. Krarup has received research support from Integra LifeSciences and Shire Pharmaceuticals Group. Dr. Boeckstyns has nothing to disclose. Dr. Ibsen has nothing to disclose. Dr. Archibald has received personal compensation for activities with Integra LifeSciences Corp. as an employee.

Hand Therapy, 2014

Introduction The purpose of this secondary analysis of pooled data from two randomised controlled... more Introduction The purpose of this secondary analysis of pooled data from two randomised controlled trials was to explore the differential rate of recovery of sensory and motor functions over time following repair of median or ulnar nerve. Methods Recovery over two years following median or ulnar nerve repair at wrist level using the Rosen score was analysed in 67 patients. Results Within the sensory domain of the Rosen score, a substantial gap was observed between recovery of touch thresholds and discriminative touch. Within the motor domain, manual muscle strength and grip strength showed a closer and more parallel recovery rate. Conclusion The differential recovery rates in touch thresholds and discriminative touch after a peripheral nerve injury are likely due to neurobiological factors that cannot be influenced by surgical interventions. However, new knowledge about brain plasticity opens up the possibility that this differential recovery may diminish through the use of revised r...

Journal of Wrist Surgery, 2015

Clinical Neurophysiology, 2016

Reestablishing motor function after complete nerve lesion is associated with extensive remodeling... more Reestablishing motor function after complete nerve lesion is associated with extensive remodeling, enlargement and unstable firing of motor units during nerve regeneration and muscle reinnervation. Force production relied on fewer and larger motor units after nerve regeneration which have implications for metabolic strain on anterior horn cells and motor fibers. Remodeling of motor units and recovery of force were similar after short nerve gap repair with a collagen nerve conduit and suture. a b s t r a c t Objective: Peripheral nerve has the capacity to regenerate after nerve lesions; during reinnervation of muscle motor units are gradually reestablished. The aim of this study was to follow the time course of reestablishing and remodeling of motor units in relation to recovery of force after different types of nerve repair. Methods: Reinnervation of muscle was compared clinically and electrophysiologically in complete median or ulnar nerve lesions with short gap lengths in the distal forearm repaired with a collagen nerve conduit (11 nerves) or nerve suture (10 nerves). Reestablishment of motor units was studied by quantitative EMG and recording of evoked compound muscle action potential (CMAP) during a 24-month observation period after nerve repair. Results: Force recovered partially to about 80% of normal. Denervation activity gradually decreased during reinnervation though it was still increased at 24 months. Nascent motor unit potentials (MUPs) at early reinnervation were prolonged and polyphasic. During longitudinal studies, MUPs remained prolonged and their amplitudes gradually increased markedly. Firing of MUPs was unstable throughout the study. CMAPs gradually increased and the number of motor units recovered to approximately 20% of normal. There was weak evidence of CMAP amplitude recovery after suture ahead of conduit repair but without treatment related differences at 2 years. Conclusions: Surgical repair of nerve lesions with a nerve conduit or suture supported recovery of force and of motor unit reinnervation to the same extent. Changes occurred at a higher rate during early regeneration and slower after 12 months but should be followed for at least 2 years to assess outcome. EMG changes reflected extensive remodeling of motor units from early nascent units to a mature state with greatly enlarged units due to axonal regeneration and collateral sprouting and maturation of regenerated nerve and reinnervated muscle fibers after both types of repair. Significance: Remodeling of motor units after peripheral nerve lesions provides the basis for better recovery of force than the number of motor axons and units. There were no differences after repair with a collagen nerve conduit and nerve suture at short nerve gap lengths. The reduced number of motor units indicates that further improvement of repair procedures and nerve environment is needed.

Scandinavian Journal of Medicine & Science in Sports, 2007

Wrist pain is a common complaint in gymnasts. Repetitive stress on the distal radial physis may l... more Wrist pain is a common complaint in gymnasts. Repetitive stress on the distal radial physis may lead to either gradual slipping of the epiphysis or growth disturbances. In some cases growth disturbances of the distal radial physis lead to triangulation of the distal radius and secondary ulnar overgrowth, and eventually a Madelung-like deformity. The present case report is the first to describe the outcome of epiphysiodesis of the distal radial and ulnar growth dates in a skeletally immature gymnast as a surgical treatment to irevent-Madelung's deformity.

The Journal of Hand Surgery, 1984

A retrospective study of the results after surgical treatment of scaphoid nonunion in two orthope... more A retrospective study of the results after surgical treatment of scaphoid nonunion in two orthopedic centers is described. One center used Bentzon &#39;s soft tissue-arthroplasty method in 15 cases, and the other center used Matti - Russe bone grafting procedure in 32 cases. Of these 47 cases, 46 had established pseudarthroses. The clinical results were similar in both methods (average follow-up time: 61.4 and 44.0 months, respectively). Soft tissue arthroplasty permitted an earlier return to work, but the risk of long-term degenerative changes developing cannot yet be excluded.

The Journal of Hand Surgery, 1985

Twenty-six patients with scaphoid nonunion were reexamined 22 to 39 years after Bentzon&#39;s... more Twenty-six patients with scaphoid nonunion were reexamined 22 to 39 years after Bentzon&#39;s soft tissue interposition arthroplasty was performed. All but one were satisfied, although three still had moderate pain. Mobility of the wrist was reduced by 20% to 25% and grip strength by 8%. The nonunion remained open and unstable in 16 of 25 radiologically reexamined cases. Carpal collapse, which had increased over time, was found in 15 cases, nine of which presented an unstable nonunion. Osteoarthritis had developed in five of 15 wrists with carpal collapse and in two of 10 without it. No significant osteoarthritis was found in any case earlier than 27 years after the operation. Thus, the risk of disability that is due to late degenerative changes of the wrist is small, even in the presence of carpal collapse.

Pain, 1989

Ninety-two knees in 46 patients were evaluated with regard to pain: in 51 of these knees, implant... more Ninety-two knees in 46 patients were evaluated with regard to pain: in 51 of these knees, implantation of a hinged endoprosthesis had been performed. The reliability and validity of 2 pain evaluation methods were assessed: the knee-pain questionnaire method (standard version including 10 questions and modified version including 14 questions) and the visual analogue scale method (standard version without numbering and O-10 scale). The visual analogue scale-standard version and O-10 scaleturned out to be more reliable than the questionnaires. The O-10 scale was the most valid when compared to the patients' own opinions regarding pain.

Danish medical journal, 2014

Treatment of base fractures in the proximal phalanx depends on the fracture type, the degree of d... more Treatment of base fractures in the proximal phalanx depends on the fracture type, the degree of displacement and whether fracture reduction is stable or not. Internal fixation often leads to decreased mobility of the injured finger despite exact reduction of the fracture. Our treatment is focused upon function and to a lesser extent on exact reposition of the fractured fifth digit. Buddy taping was used after initial, closed reduction of the fracture allowing for immediate mobilisation. This was a prospective follow-up study of 53 consecutive conservatively managed base fractures in 53 patients with a mean age of 39 years. All fractures were treated with buddy taping to the fourth digit and immediate mobilisation. The subjective outcome showed high overall satisfaction, and only four patients reported mild pain at rest or work. Malrotation was noted in three cases, none of which needed corrective surgery. All but one patient regained full flexion of the affected finger. Satisfactory...

Journal of Hand Surgery (European Volume)

evidence to support that surgery indeed speeds up recovery in all such patients because of the ra... more evidence to support that surgery indeed speeds up recovery in all such patients because of the rarity of this disorder. I agree with the approach taken by David Elliot; conservative treatment for at least 6 months and not rushing to surgery for these patients. Nowadays, some patients may not tolerate waiting for 6 months. The willingness to go through a lengthy period of conservative treatment, as well as perspectives on cost of surgery vary globally in different subsets of patients. For example, we may encounter situations where the surgeon has advised that the compression usually resolves spontaneously without surgery and the risks of surgery, but the patient still wishes to undergo surgery to achieve a possible faster recovery. Earlier surgery seems acceptable for this subset of patients when the surgeon and the patient have made a joint decision. In these situations, it is key that the patient fully understands the surgery is unnecessary for recovery and also that the surgeon had not presented surgery as a necessary or the only solution. My recommendation would be that any surgeon who encounter a case of AIN compression consider neuritis the initial diagnosis. It is entirely possible that compression of the nerve by the normal surrounding tissues simply does not exist and that nearly all or all of these patients may, in fact, have neuritis. If symptoms persist for months, surgeons should investigate for any space-occupying disorders around or in the AIN or any constriction inside the AIN with MRI or ultrasound examination. When ultrasound is available in the clinic, the nerve is best examined with ultrasound in the initial clinic visit. Finally, it is important to note that compression of the AIN, as discussed above, differs slightly from the scope of AIN syndrome (Figure 2). The latter is broader and can be caused by pathologies of the AIN (Figure 2). The disorder of pathologies occurring within the nerve does exist as reported (Pan et al., 2014), and is not caused by external compression. This letter compliments my earlier article about median nerve compression (Tang, 2021), in which I discussed FDS-pronator syndrome and lacertus syndrome. That article, however, did not include any detailed discussion of AIN compression as it is rarer, and I suspect that most or all of the patients with spontaneous recovery of AIN compression, as seen by other surgeons, might have had neuritis. Entrapment neuropathy of AIN – namely, compression by the surrounding tissues – may exist only rarely or not at all.

Journal of wrist surgery, 2020

Purpose Various implants have been described for ulnar head replacement (UHR) or for total repla... more Purpose Various implants have been described for ulnar head replacement (UHR) or for total replacement of the distal radioulnar joint (DRUJ). Many series are small and few reports on mid- or long-term results. This study is primarily aimed to report on the midterm results after ulnar head only and total DRUJ replacement using the uHead in the treatment of painful disorders of the DRUJ. The secondary aim of the study was to eventually assess the combination of UHR and total wrist arthroplasty (TWA). Materials and Methods We included 20 consecutive patients in whom an UHR with the uHead was performed at our institution between February 2005 and March 2017. There were 6 men and 14 women with mean age of 59 years (range: 36-80 years). The mean follow-up time was 5 years (range: 2-15 years). Data were recorded prospectively before operation and at follow-up examinations and entered in a registry. The patients were followed-up at 3 and 6 weeks and 3, 6, and 12 months postoperatively and...

Hand Clinics, 2017

Wrist arthroplasty provides functional mobility, improved strength and upper limb function, and r... more Wrist arthroplasty provides functional mobility, improved strength and upper limb function, and reduced pain in carefully selected cases of severely destroyed wrist joints. Indications are severe wrist destruction due to rheumatoid arthritis (RA), idiopathic osteoarthritis (OA), scapholunate advanced collapse (SLAC) wrist, malunited intra-articular distal radius fractures, acute irreparable distal radius fractures in the elderly, and Kienbö ck disease. High physical demand, young age, poor bone stock, and spontaneously fused wrist in patients with RA are generally contraindications. Implant survival rates have improved with the latest designs but do not compare with the survival rates of hip and knee arthroplasties.

Journal of Hand Surgery (European Volume), 2019

Annals of Neurology, 2017

Objective: Sensation is essential for recovery after peripheral nerve injury. However, the relati... more Objective: Sensation is essential for recovery after peripheral nerve injury. However, the relationship between sensory modalities and function of regenerated fibers is uncertain. We have investigated the relationships between touch threshold, tactile gnosis and mechanoreceptor and sensory fiber function after nerve regeneration. Methods: Twenty-one median or ulnar nerve lesions were repaired by a collagen nerve conduit or direct suture. Quantitative sensory hand function and sensory conduction studies by near-nerve technique including tactile stimulation of mechanoreceptors were followed for 2 years, and results were compared to non-injured hands. Results: At both repair methods, touch thresholds at the finger tips recovered to 81±3% and tactile gnosis only to 20±4% (P<0.001) of control. The sensory action potentials (SNAPs) remained dispersed and areas recovered to 23±2% and the amplitudes only to 7±1% (P<0.001). The areas of SNAPs after tactile stimulation recovered to 61±11% and remained slowed. Touch sensation correlated with SNAP areas (P<0.005) and was negatively related to the prolongation of tactile latencies (P<0.01); tactile gnosis was not related to electrophysiological parameters. Interpretation: The recovered function of regenerated peripheral nerve fibers and reinnervated mechanoreceptors may differentially influence recovery of sensory modalities. Touch was affected by the number and function of regenerated fibers and mechanoreceptors. In contrast, tactile gnosis depends on the input and plasticity of the CNS, which may explain the absence of a direct relation between electrophysiological parameters and poor recovery. Dispersed maturation of sensory nerve fibers with desynchronized inputs to the CNS also contributes to the poor recovery of tactile gnosis.

Clinical Neurophysiology, 2018

Introduction: The reports on tremor and different types of polyneuropathies have been increasing ... more Introduction: The reports on tremor and different types of polyneuropathies have been increasing and it was suggested to be associated with cerebellar involvement in chronic inflammatory demyelinating polyneuropathy (CIDP). Apart from specific syndromes, the coexistence of polyneuropathy and myoclonus is exceptional. We previously observed cortical myoclonus in cases with inflammatory polyneuropathy who were referred for tremor analysis and aimed to analyze presence of myoclonus and its relation with clinical features in demyelinating polyneuropathies. Methods: We prospectively included all patients with inflammatory polyneuropathy who were admitted between January 2017 and June 2017 and had tremor-like, regular or irregular involuntary movements on clinical examination. All patients underwent neurological examination and multichannel surface electromyography which included upper extremity muscles as well as lower extremity and facial or neck muscles in selected cases. We also recorded long latency reflexes and somatosensory evoked potentials (SEPs) to categorize myoclonus. Results: We identified eight patients with demyelinating polyneuropathy who matched the inclusion criteria: four patients with CIDP, three patients with Guillain-Barre syndrome and one patient with Charcot-Marie-Tooth disease. The mean age was 50.5 ± 19.6 years (range: 26-81 years) and there were seven male patients. Seven out of eight patients had myoclonus, two of which were in the form of polyminimyoclonus. Others had myoclonus on both proximal and distal parts of upper extremities. Negative myoclonus was observed in four of them. Duration of myoclonus was between 30 and 100 ms. only one had duration of 200 ms. Most patients (five out of seven) had cortical myoclonus (with high-amplitude C reflex or SEPs). Conclusion: Myoclonus in the patients with polyneuropathy was irregular tremor-like, however, the electrophysiological characteristics was similar to a cortical subtype. Therefore, it would be interesting to investigate a bigger cohort of inflammatory polyneuropathies for the presence and subtypes of myoclonus and to determine associated clinical features.

Hand Clinics, 2017

Common hand problems are treated differently in different countries. This article attempts to bri... more Common hand problems are treated differently in different countries. This article attempts to bring together the views of surgeons from different countries on some of the most common hand problems that hand surgeons encounter in daily The authors have nothing to disclose.

Scandinavian Journal of Plastic and Reconstructive Surgery and Hand Surgery, 2000

Seventy-six consecutive patients were operated on for advanced Dupuytren's contracture and the re... more Seventy-six consecutive patients were operated on for advanced Dupuytren's contracture and the results evaluated after nine months with special reference to the use of a dynamic extension splint. The patients were separated into three groups: those in whom the splint was used according to our guidelines (n = 15); those in whom the splint was used, but inadequately (n = 15); and those who did not require splinting (n = 24). Our results nine months postoperatively were similar to those of other studies in showing that the fifth proximal interphalangeal joint constituted the greatest problem. Comparison of the three groups indicated that splinting the way we used it did not influence the natural course of the disease after operation.

Chirurgie de la Main, 2015

Introduction Third generation implants for total wrist arthroplasty (TWA) has now been available ... more Introduction Third generation implants for total wrist arthroplasty (TWA) has now been available for more than 17 years. Consequently, an increasing number need revision. Aims of the study To report on our experience with revision surgery after failed TWA. Methods We prospectively and consecutively collected data on all TWA's that were revised in two clinics and made a general follow-up examination in May–June 2015. Findings We revised a total of 19 cases - 8 with rheumatoid arthritis, 11 with other diagnoses. Twelve were revised to a remotion TWA, 1 to an Amandys interposition implant and 6 were fused. At final follow-up, at an average of 31 months after operation, median improvement in QuickDASH score was 25 points, median improvement in VAS score for pain was 50 points. Three revisions TWA had been re-revised and 1 was loose and scheduled for re-revision. There was no difference in QuickDASH- or in VAS score between patients with fusion and patients with TWA. Conclusions Both fusion and revision to a new TWA are feasible after a failed TWA. Revision to a new TWA may require supplementary major procedures.

Neurology, Apr 8, 2014

OBJECTIVE: We investigated reinnervation of muscle fibers and subsequent remodeling of the motor ... more OBJECTIVE: We investigated reinnervation of muscle fibers and subsequent remodeling of the motor unit after complete nerve lesions. EMG was carried out in ulnar or median innervated muscles after nerve-repair by suture or a collagen nerve guide. BACKGROUND: After complete nerve lesions peripheral nerve fibers regenerate. Recovery is dependent of the rate of growth of fibers, the number of axons that regenerate, innervation of target tissue and maturation of regenerated fibers. Recovery is often incomplete, and patients have lasting motor deficits. DESIGN/METHODS: In this randomized multi-center study two procedures for repair of complete nerve lesions were compared. The collagen nerve guide (NeuraGen™) was implanted in 22 of 43 patients and direct suture repair was used in 20 patients and a short graft in 1 patient. The outcome measures included clinical and electrophysiological studies at 1, 3, 6, 12, 18 and 24 months after repair. In a subgroup of 10 nerves repaired by suture and in 11 by nerve guide, quantitative EMG was assessed. A concentric needle was inserted in the muscle at up to 10 sites and the decomposition system EMGtools was used for analysis (IEEE TBE, 2011, 58:2707-2718). We measured denervation; durations, shapes and amplitudes of motor unit potentials (MUPs); and amplitudes and shapes of the recruitment patterns at maximal effort. The parameters were compared with normal controls and the contralateral normal muscle. RESULTS: Denervation activity and absent voluntary activity occurred in all patients at 1 months. MUPs of small amplitude, long duration and polyphasic shape were first recorded after 3-6 months. Denervation gradually decreased and the amplitudes of the MUPs gradually increased while the duration remained unchanged. The amplitude and interference of the recruitment pattern increased. No differences at different repair types were detected. CONCLUSIONS: Regeneration over short gap was supported as well by nerve guide as by suture and in the patient groups muscle reinnervation was similar. Study Supported by: Integra LifeSciences, Corp. Disclosure: Dr. Krarup has received personal compensation for activities with Integra LifeSciences as a speaker, and Abbott Laboratories Inc. as an advisory board member. Dr. Krarup has received research support from Integra LifeSciences and Shire Pharmaceuticals Group. Dr. Boeckstyns has nothing to disclose. Dr. Ibsen has nothing to disclose. Dr. Archibald has received personal compensation for activities with Integra LifeSciences Corp. as an employee.

Hand Therapy, 2014

Introduction The purpose of this secondary analysis of pooled data from two randomised controlled... more Introduction The purpose of this secondary analysis of pooled data from two randomised controlled trials was to explore the differential rate of recovery of sensory and motor functions over time following repair of median or ulnar nerve. Methods Recovery over two years following median or ulnar nerve repair at wrist level using the Rosen score was analysed in 67 patients. Results Within the sensory domain of the Rosen score, a substantial gap was observed between recovery of touch thresholds and discriminative touch. Within the motor domain, manual muscle strength and grip strength showed a closer and more parallel recovery rate. Conclusion The differential recovery rates in touch thresholds and discriminative touch after a peripheral nerve injury are likely due to neurobiological factors that cannot be influenced by surgical interventions. However, new knowledge about brain plasticity opens up the possibility that this differential recovery may diminish through the use of revised r...

Journal of Wrist Surgery, 2015

Clinical Neurophysiology, 2016

Reestablishing motor function after complete nerve lesion is associated with extensive remodeling... more Reestablishing motor function after complete nerve lesion is associated with extensive remodeling, enlargement and unstable firing of motor units during nerve regeneration and muscle reinnervation. Force production relied on fewer and larger motor units after nerve regeneration which have implications for metabolic strain on anterior horn cells and motor fibers. Remodeling of motor units and recovery of force were similar after short nerve gap repair with a collagen nerve conduit and suture. a b s t r a c t Objective: Peripheral nerve has the capacity to regenerate after nerve lesions; during reinnervation of muscle motor units are gradually reestablished. The aim of this study was to follow the time course of reestablishing and remodeling of motor units in relation to recovery of force after different types of nerve repair. Methods: Reinnervation of muscle was compared clinically and electrophysiologically in complete median or ulnar nerve lesions with short gap lengths in the distal forearm repaired with a collagen nerve conduit (11 nerves) or nerve suture (10 nerves). Reestablishment of motor units was studied by quantitative EMG and recording of evoked compound muscle action potential (CMAP) during a 24-month observation period after nerve repair. Results: Force recovered partially to about 80% of normal. Denervation activity gradually decreased during reinnervation though it was still increased at 24 months. Nascent motor unit potentials (MUPs) at early reinnervation were prolonged and polyphasic. During longitudinal studies, MUPs remained prolonged and their amplitudes gradually increased markedly. Firing of MUPs was unstable throughout the study. CMAPs gradually increased and the number of motor units recovered to approximately 20% of normal. There was weak evidence of CMAP amplitude recovery after suture ahead of conduit repair but without treatment related differences at 2 years. Conclusions: Surgical repair of nerve lesions with a nerve conduit or suture supported recovery of force and of motor unit reinnervation to the same extent. Changes occurred at a higher rate during early regeneration and slower after 12 months but should be followed for at least 2 years to assess outcome. EMG changes reflected extensive remodeling of motor units from early nascent units to a mature state with greatly enlarged units due to axonal regeneration and collateral sprouting and maturation of regenerated nerve and reinnervated muscle fibers after both types of repair. Significance: Remodeling of motor units after peripheral nerve lesions provides the basis for better recovery of force than the number of motor axons and units. There were no differences after repair with a collagen nerve conduit and nerve suture at short nerve gap lengths. The reduced number of motor units indicates that further improvement of repair procedures and nerve environment is needed.

Scandinavian Journal of Medicine & Science in Sports, 2007

Wrist pain is a common complaint in gymnasts. Repetitive stress on the distal radial physis may l... more Wrist pain is a common complaint in gymnasts. Repetitive stress on the distal radial physis may lead to either gradual slipping of the epiphysis or growth disturbances. In some cases growth disturbances of the distal radial physis lead to triangulation of the distal radius and secondary ulnar overgrowth, and eventually a Madelung-like deformity. The present case report is the first to describe the outcome of epiphysiodesis of the distal radial and ulnar growth dates in a skeletally immature gymnast as a surgical treatment to irevent-Madelung's deformity.