Ahmed Enan - Academia.edu (original) (raw)

Papers by Ahmed Enan

The Role of Osteotomy in the Correction of Congenital and Acquired Disorders of the Skeleton, 2012

Hallux valgus is a common disorder of the forefoot that results from medial deviation of the firs... more Hallux valgus is a common disorder of the forefoot that results from medial deviation of the first metatarsal and lateral deviation and / or rotation of the great toe (hallux) with or without medial soft-tissue enlargement of the first metatarsal head (bunion) (1). 2. Potential etiology The pathogenesis of hallux valgus has been described as being due to muscle imbalance. A. Extrinsic factors Hallux valgus occurs almost exclusively in shoe-wearing societies. Coughlin and Thompson (2) noting the extremely high prevalence of bunions in American women in the fourth, fifth or sixth decade of life, implicated constricting footwear as a cause of hallux valgus. Likewise, in Japan, Kato and Watanabe (3) noted that the prevalence of hallux valgus in women increased dramatically following the introduction of high-fashion footwear after World War II. B. Intrinsic factors While constricting footwear appears to be the major extrinsic cause of hallux valgus, intrinsic factors play a role as well. Inman (4) and Hohmann (5) both suggested pronation of the hindfoot as a major cause of bunion formation, while Mann and Coughlin (6) as well as others (7,8) reported that pes planus plays a minor role in this process. An increased angle between the first and second metatarsals (metatarsus primus varus) is often associated with hallux valgus deformity. (9) Other intrinsic causes of Hallux valgus may include contracture of the Achilles tendon, generalized joint laxity, hypermobility of the first metatarsocuneiform joint, and neuromuscular disorders (including cerebral palsy and stroke). (10) Heredity is thought to influence the development of hallux valgus in many individuals. Hardy and Clapham noted that 63 % of the patients in their series had a parent who had hallux valgus. (9) The primary symptom of hallux valgus is pain over the medial eminence. Pressure from footwear is the most frequent cause of this discomfort. 2.1 Measurements of the deformity Two angles frequently are used to describe the anatomical deformity and the effects of a surgical procedure: the first intermetatarsal angle (IMA) and the hallux valgus angle (HVA). www.intechopen.com The Role of Osteotomy in the Correction of Congenital and Acquired Disorders of the Skeleton 262 Authors classify mild as an IMA < 13°, moderate as IMA 13-20°, and severe as an IMA > 20°. Generally, a HVA > 40° is considered severe. (11) 2.2 Surgical treatment The condition is widely reported in the Western literature. The incidence of hallux valgus was as high as 50 % in a study in South Africans (12) and as low as 2 % in a study on barefoot population. (13) Nonoperative treatment is always the first option for a patient with hallux valgus deformity. Surgery is proposed when the painful hallux valgus is not adequately controlled by the nonoperative treatment. Over the past century, around 150 surgical procedures have been developed to reduce the deformity, and the continued development of new techniques would suggest that previous techniques are not completely successful. Poorly planned or executed surgery may lead to high levels of patient dissatisfaction. In the last few years, several new osteotomies have been described, but often it is difficult to ascertain what the best choice for a given patient is, as evidence-based guidelines are lacking.(1) The main goal of surgical correction of hallux valgus is the morphologic and functional rebalance of the first ray, correcting all other characteristics of the deformity. Historically, distal metatarsal osteotomies have been indicted in cases of mild or moderate deformity with an intermetatarsal angle as large as 15°. Using certain osteotomies, it is possible to correct intermetatarsal angles as large as 20°. Distal osteotomies may also be used to correct deformities characterized by deviation of the distal metatarsal articular angle (DMAA) or to address concomitant stiffness.(14) Since the first operation published by Revenrdin (15) in 1881, many authors have reported their experience using different operations, each of them characterized by different indications, approaches, designs, and fixation.(16-24) There is an increasing concern among orthopaedists towards the potentials of minimally invasive procedures. Applied to foot surgery, minimally invasive surgery (MIS) can be accomplished is shorter time respect of a conventional surgery, together with less distress and problems to the soft tissues. In addition, the operation can be done bilaterally; it allows use of distal anaesthetics blocks and early weight-bearing. In 1986, Van Enoo defined the minimum-incision surgery as an operation done through the smallest incision required for a proper procedure, and the percutaneous surgery as that performed within the smallest possible working incision in a closed fashion. (25) A percutaneous MIS requires the use of dedicated instruments and frequently a fluoroscopy. Lui and other colleagues from Hong Kong have described arthroscopic and endoscopic assisted correction of hallux valgus deformities. (26, 27) Morton Polokoff, a podiatric physician, in 1945 tried to use fine chisels, rasps and spears to perform subdermal surgery. Years later, Leonard Britton accomplished the first osteotomy on bunion deformities with percutaneous exposure of the first metatarsal, a closing wedge osteotomy, and the Akin procedure. North American podiatrists started to adopt MIS of the foot in 1970.(28) The technique percutaneous surgery for hallux valgus correction that we use derives from that described by Lamprecht-Kramer-Bösch in 1982.(16,29) These authors based the procedure on the subcapital metatarsal linear osteotomy of Hohmann.(30) In 1991, Isham described a minimally invasive distal metatarsal osteotomy without implantation.(31) The results of recent French studies showed that patients treated with minimally invasive surgery for hallux valgus needed less hospitalization time and recovered earlier.(32) Minimum incision techniques, by allowing limb safety with reduced damage of soft tissue www.intechopen.com Minimally Invasive Distal Metatarsal Osteotomy for Mild-to-Moderate Hallux Valgus 263 or bones trauma should be a first choice indication to patients at high risk of ulceration.(33,34) The characteristics of this technique can be summarized with the abbreviation SERI (simple, effective, rapid, inexpensive).

The Role of Osteotomy in the Correction of Congenital and Acquired Disorders of the Skeleton, 2012

Hallux valgus is a common disorder of the forefoot that results from medial deviation of the firs... more Hallux valgus is a common disorder of the forefoot that results from medial deviation of the first metatarsal and lateral deviation and / or rotation of the great toe (hallux) with or without medial soft-tissue enlargement of the first metatarsal head (bunion) (1). 2. Potential etiology The pathogenesis of hallux valgus has been described as being due to muscle imbalance. A. Extrinsic factors Hallux valgus occurs almost exclusively in shoe-wearing societies. Coughlin and Thompson (2) noting the extremely high prevalence of bunions in American women in the fourth, fifth or sixth decade of life, implicated constricting footwear as a cause of hallux valgus. Likewise, in Japan, Kato and Watanabe (3) noted that the prevalence of hallux valgus in women increased dramatically following the introduction of high-fashion footwear after World War II. B. Intrinsic factors While constricting footwear appears to be the major extrinsic cause of hallux valgus, intrinsic factors play a role as well. Inman (4) and Hohmann (5) both suggested pronation of the hindfoot as a major cause of bunion formation, while Mann and Coughlin (6) as well as others (7,8) reported that pes planus plays a minor role in this process. An increased angle between the first and second metatarsals (metatarsus primus varus) is often associated with hallux valgus deformity. (9) Other intrinsic causes of Hallux valgus may include contracture of the Achilles tendon, generalized joint laxity, hypermobility of the first metatarsocuneiform joint, and neuromuscular disorders (including cerebral palsy and stroke). (10) Heredity is thought to influence the development of hallux valgus in many individuals. Hardy and Clapham noted that 63 % of the patients in their series had a parent who had hallux valgus. (9) The primary symptom of hallux valgus is pain over the medial eminence. Pressure from footwear is the most frequent cause of this discomfort. 2.1 Measurements of the deformity Two angles frequently are used to describe the anatomical deformity and the effects of a surgical procedure: the first intermetatarsal angle (IMA) and the hallux valgus angle (HVA). www.intechopen.com The Role of Osteotomy in the Correction of Congenital and Acquired Disorders of the Skeleton 262 Authors classify mild as an IMA < 13°, moderate as IMA 13-20°, and severe as an IMA > 20°. Generally, a HVA > 40° is considered severe. (11) 2.2 Surgical treatment The condition is widely reported in the Western literature. The incidence of hallux valgus was as high as 50 % in a study in South Africans (12) and as low as 2 % in a study on barefoot population. (13) Nonoperative treatment is always the first option for a patient with hallux valgus deformity. Surgery is proposed when the painful hallux valgus is not adequately controlled by the nonoperative treatment. Over the past century, around 150 surgical procedures have been developed to reduce the deformity, and the continued development of new techniques would suggest that previous techniques are not completely successful. Poorly planned or executed surgery may lead to high levels of patient dissatisfaction. In the last few years, several new osteotomies have been described, but often it is difficult to ascertain what the best choice for a given patient is, as evidence-based guidelines are lacking.(1) The main goal of surgical correction of hallux valgus is the morphologic and functional rebalance of the first ray, correcting all other characteristics of the deformity. Historically, distal metatarsal osteotomies have been indicted in cases of mild or moderate deformity with an intermetatarsal angle as large as 15°. Using certain osteotomies, it is possible to correct intermetatarsal angles as large as 20°. Distal osteotomies may also be used to correct deformities characterized by deviation of the distal metatarsal articular angle (DMAA) or to address concomitant stiffness.(14) Since the first operation published by Revenrdin (15) in 1881, many authors have reported their experience using different operations, each of them characterized by different indications, approaches, designs, and fixation.(16-24) There is an increasing concern among orthopaedists towards the potentials of minimally invasive procedures. Applied to foot surgery, minimally invasive surgery (MIS) can be accomplished is shorter time respect of a conventional surgery, together with less distress and problems to the soft tissues. In addition, the operation can be done bilaterally; it allows use of distal anaesthetics blocks and early weight-bearing. In 1986, Van Enoo defined the minimum-incision surgery as an operation done through the smallest incision required for a proper procedure, and the percutaneous surgery as that performed within the smallest possible working incision in a closed fashion. (25) A percutaneous MIS requires the use of dedicated instruments and frequently a fluoroscopy. Lui and other colleagues from Hong Kong have described arthroscopic and endoscopic assisted correction of hallux valgus deformities. (26, 27) Morton Polokoff, a podiatric physician, in 1945 tried to use fine chisels, rasps and spears to perform subdermal surgery. Years later, Leonard Britton accomplished the first osteotomy on bunion deformities with percutaneous exposure of the first metatarsal, a closing wedge osteotomy, and the Akin procedure. North American podiatrists started to adopt MIS of the foot in 1970.(28) The technique percutaneous surgery for hallux valgus correction that we use derives from that described by Lamprecht-Kramer-Bösch in 1982.(16,29) These authors based the procedure on the subcapital metatarsal linear osteotomy of Hohmann.(30) In 1991, Isham described a minimally invasive distal metatarsal osteotomy without implantation.(31) The results of recent French studies showed that patients treated with minimally invasive surgery for hallux valgus needed less hospitalization time and recovered earlier.(32) Minimum incision techniques, by allowing limb safety with reduced damage of soft tissue www.intechopen.com Minimally Invasive Distal Metatarsal Osteotomy for Mild-to-Moderate Hallux Valgus 263 or bones trauma should be a first choice indication to patients at high risk of ulceration.(33,34) The characteristics of this technique can be summarized with the abbreviation SERI (simple, effective, rapid, inexpensive).