O Foot and ankle Percutaneous screw fixation for fractures of the
Transcription
O Foot and ankle Percutaneous screw fixation for fractures of the
Foot and ankle Percutaneous screw fixation for fractures of the sesamoid bones of the hallux C. M. Blundell, P. Nicholson, M. W. Blackney From the Monash Medical Centre, Clayton, Australia ver a period of one year we treated nine fractures of the sesamoid bones of the hallux, five of which were in the medial sesamoid. All patients had symptoms on exercise, but only one had a recent history of injury. The mean age of the patients was 27 years (17 to 45) and there were six men. The mean duration of symptoms was nine months (1.5 to 48). The diagnosis was based on clinical and radiological investigations. We describe a new surgical technique for percutaneous screw fixation for these fractures using a Barouk screw. All the patients were assessed before and after surgery using the American Orthopaedic Foot and Ankle Society Hallux Score (AOFAS). There was a statistically significant improvement in the mean score from 46.9 to 80.7 (p = 0.0003) after fixation of the fracture with a rapid resolution of symptoms. All patients returned to their previous level of activity by three months. We believe that this relatively simple technique is an excellent method of treatment in appropriately selected patients. O J Bone Joint Surg [Br] 2002; 84-B:1138-41. Submitted: 5 December 2001; Accepted: 12 April 2002 Fractures of the sesamoids are one of many conditions which can present in the metatarsal region with disabling pain related to exercise. The symptoms can be devastating, particularly to a high-performance athlete.1 An accurate diagnosis should be based on thorough clinical examination and radiological investigations. C. M. Blundell, FRCS (Trauma & Orth), Foot and Ankle Fellow P. Nicholson, FRCS Orth, Fellow M. W. Blackney, FRACS, Consultant Orthopaedic Surgeon Department of Orthopaedics, Monash Medical Centre, 246 Clayton Road, Clayton, Victoria 3168, Australia. Correspondence should be sent to Mr C. M. Blundell at 44 Christchurch Road, Norwich, Norfolk NR2 3NE, UK. ©2002 British Editorial Society of Bone and Joint Surgery 0301-620X/02/813064 $2.00 1138 The optimal management of these fractures is unclear, and patients are often initially treated conservatively,2,3 with methods which include strapping, immobilisation in a cast, orthotics, steroid injections and modification of activity. If the symptoms fail to settle, surgical alternatives may be considered, particularly in high-performance athletes.1,4 These include total or partial excision of the sesamoid or bone grafting of nonunion.1,2,4,5 The uncertain outcome following these procedures led us to look for an alternative treatment. We now describe a new technique of percutaneous screw fixation of fractures of the sesamoid bones of the hallux. Patients and Methods We have treated nine fractures of the sesamoid bones of the hallux by percutaneous fixation. In all patients the fracture was in the sagittal plane, i.e. transverse to the tendon of flexor hallucis brevis, and comminution was minimal. Seven were high-performance athletes (Table I) and five competed at interstate or national level. Their mean age was 27 years (17 to 45) and there were six men. They complained of pain of gradual onset on the plantar aspect of the first metatarsophalangeal joint on exercise. In only one patient was there a previous history of injury. The mean duration of symptoms was nine months (six weeks to four years). The median duration was three months. The patients were assessed using the American Orthopaedic Foot and Ankle Society Hallux Score (AOFAS) (Table II)6 and the mean preoperative score was 46.9 (25 to 64). Seven graded their pain as severe and two as moderate. Clinical examination revealed tenderness over the symptomatic sesamoid, with no restriction of movement. Pain was elicited in all patients on forced dorsiflexion of the great toe. Plain radiographs, including the contralateral foot, were taken to exclude bilateral developmental lesions of the sesamoids. Anteroposterior (AP), lateral and axial weight-bearing views were obtained. In addition, all patients had a technetium bone scintigram and four had MRI and one CT. There was a fracture of the medial sesamoid in five patients and of the lateral sesamoid in four. In none were the fragments widely displaced. All patients had had a previous course of conservative treatment which failed including one or more of rest, orthotics, immobilisation in a cast, physioTHE JOURNAL OF BONE AND JOINT SURGERY PERCUTANEOUS SCREW FIXATION FOR FRACTURES OF THE SESAMOID BONES OF THE HALLUX Table I. The activities of the patients Activity Number Hockey* AFL football* Badminton* Dancing PE teacher Labourer Student 2 2 1 1 1 1 1 *national/interstate level therapy, oral analgesics, oral non-steroidal anti-inflammatory drugs and cortisone injections. Operative treatment. The procedure is carried out as a day case under general anaesthesia. No tourniquet is required. The patient is placed supine on a radiolucent operating table to allow access for an image intensifier. The great toe is strapped in maximal dorsiflexion before cleansing over the tape and draping the foot (Fig. 1a). This position stabilises the sesamoids and renders them more superficial. Axial and lateral views are obtained using the image intensifier. A stab incision is made over the distal part of the affected sesamoid. A 1 mm guide wire is inserted under radiological control into the axial and lateral mid-diameter of the sesamoid (Fig. 1b). Through the same incision a second wire of the same length is inserted and positioned at the distal cortex of the sesamoid. By comparing the protruding lengths of the wires a screw of appropriate size is selected. A 2 mm cannulated drill is inserted over the guide-wire and both cortices drilled. A self-tapping Barouk screw (DePuy International, Leeds, UK) is inserted from distal to proximal in order to engage both cortices for maximal compression. The distal thread should be buried within the sesamoid (Fig. 2). Steristrip is applied to the skin and a light dressing applied. Postoperatively, patients are mobilised with two crutches for one week, bearing weight as tolerated. They are then allowed to bear weight fully without aids. Running is allowed at six weeks with a gradual return to full activity at three months. Results There were no intraoperative failures of insertion of the screw and no wound complications. At review at three months, five patients had regained full movement of their first metatarsophalangeal joint and four had mild stiffness. All patients had dramatic relief from pain. Five were painfree and four had only mild, occasional pain. Because of compression of the fracture it was not possible to confirm union radiologically. The reduction of both the activityrelated pain and tenderness at the site of the fracture indicated that bony stability had been achieved. The mean AOFAS improved from 46.9 before to 80.7 after operation, which was statistically significant (paired Student’s t-test, p VOL. 84-B, No. 8, NOVEMBER 2002 1139 = 0.0003). At six months after surgery, all patients had returned to their preinjury recreational and sporting level of activity and had had no complications. Discussion The sesamoids have a vital role in the dynamics of the great toe since they act as a fulcrum to increase the mechanical advantage of the tendon of flexor hallucis brevis. They also absorb weight-bearing forces from the metatarsal head. The great toe complex transmits more than 50% of the bodyweight on exercise.7 The sesamoids are thus subjected to significant forces on impact loading and shear which make them susceptible to acute and stress fractures and possible subsequent nonunion. Fractures of the sesamoids are initially treated conservatively.2,3 If symptoms fail to settle, surgery may be required. The uncertain outcome following excision of a Table II. The AOFAS for grading clinical results before and after percutaneous screw fixation for fractures of the sesamoid bones of the hallux Score Pain (40 points) None Mild, occasional Moderate, daily Severe, almost always present Function (45 points) Activity limitations (10 points) No activity limitations No limitations of daily activities such as employment responsibilities, limitation of recreational activities Limited daily and recreational activities Severe limitation of daily and recreational activities 40 30 20 0 10 7 4 0 Footwear requirements (10 points) Fashionable, conventional shoes, no insert required Comfortable footwear, shoe insert Modified shoes or brace 10 5 0 MTP joint motion (dorsiflexion plus plantar flexion) Normal or mild restriction Moderate restriction Severe restriction 10 5 0 IP joint motion (plantar flexion) No restriction Severe restriction (less than 10˚) 5 0 Great toe stability (5 points) Stable Grossly unstable (floppy) 5 0 Great toe callus (5 points) Absent Present 5 0 Alignment (15 points) Good Fair Poor 15 8 0 1140 C. M. BLUNDELL, P. NICHOLSON, M. W. BLACKNEY Fig. 1a Fig. 1b Photograph showing the great toe dorsiflexed with tape. A lateral view showing the guide-wire used to aid insertion of the percutaneous screw. Fig. 2b Fig. 2a AP (a) and lateral (b) radiographs taken after surgery showing the position of the screw. sesamoid1,5 has led to more conservative procedures such as partial sesamoidectomy2 and bone grafting of nonunions.1,4 Wound complications are, however, common after these open procedures. The assessment and accurate diagnosis of the cause of sesamoid pain and subsequent management are a challenge for the orthopaedic surgeon. Differential diagnoses include acute fractures, nonunion and stress fractures. Histological examination of 32 sesamoids excised for pain showed that in 28 there was an ununited fracture, suggesting that fractures are an often undiagnosed cause of pain.8 Many authors have suggested that differentiation between the types of fracture is important with respect to management and advocate the use of bone scintigraphy, MRI and CT.4,9,10 We did not find these techniques to be particularly useful for the identification THE JOURNAL OF BONE AND JOINT SURGERY PERCUTANEOUS SCREW FIXATION FOR FRACTURES OF THE SESAMOID BONES OF THE HALLUX of the type of fracture. It is likely that our series includes patients with acute fractures, nonunions and stress fractures. We have treated all by percutaneous fixation and have achieved excellent results. We therefore question the importance of diagnosing the aetiology of the fracture. The percutaneous technique using the Barouk screw is relatively simple and free from complications. We have demonstrated an early resolution of symptoms, a rapid return to sport and a statistically significant functional improvement using the AOFAS. We agree with other authors that the sesamoids are critical to the preservation of the function of the great toe, particularly in high-performance athletes.11 The procedure described restores the integrity of the sesamoid in a relatively atraumatic fashion, without compromising function. We recommend this technique for active individuals with fractures in whom the line of the fracture is orientated predominantly transversely without comminution. Seven of our nine patients were high-performance athletes. The management of fractures of the sesamoids in such patients is acknowledged to be difficult and we were therefore encouraged by our results using this new percutaneous technique. VOL. 84-B, No. 8, NOVEMBER 2002 1141 No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article. References 1. McBryde AM Jr, Anderson RB. Sesamoid foot disorders in the athlete. Clin Sports Med 1988;7:51-60. 2. Van Hal M. Keene JS, Lange TA, Clancy WG Jr. Stress fractures of the great toe sesamoids. Am J Sports Med 1982;10:122-8. 3. Weiss JS. Fracture of the medial sesamoid of the great toe: controversies in therapy. Orthopaedics 1991;14:1003-7. 4. Anderson RB, McBryde AM. Autogenous bone grafting of hallux sesamoid non-unions. Foot Ankle Int 1997;18:293-6. 5. Kliman ME, Gross AE, Pritzker KP, Greyson ND. Osteochondritis of the hallux sesamoid bones. Foot Ankle 1983;3:220-3. 6. Kitaoka HB, Alexander IJ, Adelaar RS, et al. Clinical rating systems for the ankle-hindfoot, midfoot, hallux, and lesser toes. Foot Ankle Int 1994;15:349-53. 7. Coughlin MJ, Mann RA. Arthrodesis of the first metatarsophalangeal joint as salvage for the failed Keller procedure. J Bone Joint Surg [Am] 1987;69-A:68-75. 8. Brodsky JW, Robinson AHN, O’Krause J, Watkins D. Excision and flexor hallucis brevis reconstruction for painful sesamoid fractures and non-unions: surgical technique, clinical results and histopathological findings. J Bone Joint Surg [Br] 2000;82-B Supp III;21. 9. Feldman F, Pochaczevsky R, Hecht H. The case of the wandering sesamoid and other sesamoid afflictions. Radiology 1970;96:275-83. 10. Karasick D, Schweitzer ME. Disorders of the hallux sesamoid complex: MR features. Skeletal Radiol 1998;27:411-8. 11. Oloff LM, Schulhofer SD. Sesamoid complex disorders. Clin Podiatr Med Surg 1996;13:497-513.