Purpose: Two questions arise after metatarsophalangeal hallux arthrodesis: what are the 3D changes observed when walking on flat ground ? and is the arthrodesis compensation essentially at the talocrural or interphalangeal level ?

Material and methods: Our series included twelve patients (ten women and two men) mean age 60.7 years. Nine patients had unilateral arthrodesis and three bilateral arthrodesis. The optoelectronic exploration was conducted barefoot. The patients wore underclothes and 27 reflectors. A miniaturised reflector was placed on the distal end of each hallux. Three valid recordings were made.

Results: General gait parameters and kinematic and kinetic values were unchanged (excepting nonsignificant maximal ankle dorsiflexion). On the arthrodesis side we observed: significant decline in propulsion force in the anteroposterior and vertical planes; significantly later heel lift-off; systematic anterior displacement of the ground reaction force of the metatarsophalangeal joint (not seen on the healthy side).

Discussion: We propose a coherent explanation of these observations. The kinetics of balance movement under the head of the first metatarsal head is changed. When the foot is flat on the ground, as the ankle balance movement occurs, the weight of the body is transferred earlier and massively to the forefoot. While in the healthy foot this occurs under the metatarsophalangeal joint of the great toe, in arthrodesis patients body weight is transferred under the interphalangeal joint of the great toe. The balance movement of the interphalangeal joint of the great toe occurs when the ankle balance movement is terminated. The centre of the balance movement is more distal and heel lift-off tends to occur later. During the propulsion phase, the greater lever arm limits the propulsion force, explaining the lesser peak force observed on the arthrodesis side. Use of reflectors on the distal end of the hallux demonstrated that the arthrodesis compensation occurs essentially at the interphalangeal level, exposing this joint to greater risk of degeneration.

Purpose: The purpose of this retrospective analysis over a seven-year period was to evaluate outcome of centromedullary nailing without reaming using the UTN for leg fractures.

Material and methods: A nailing procedure was performed in 106 patients (71 men and 35 women), mean age 38.2 years (16–76); 31.1% had multiple trauma injuries. Fractures were closed (77.4%) or open (22.6%): Gustilo I (n=19), Gustilo II (n=5). The fracture involved the shaft (77.4%), the lower quarter of the tibia (12.2%) or was bifocal (10.3%). There were five cases of vessel injury at diagnosis and two cases of neurological injury. A static assembly was used in all cases. Weight-bearing was resumed after a 6-week period of rest before unlocking.

Results: Mean follow-up was 13.1 months. Bone healing was achieved in 85.8% of the cases in 17 weeks on average. There were five cases of deformed callus (5–10° valgus or varus which did not require surgical revision). Late healing was noted in 7.5% and true nonunion in 6.6% which required either fibular osteotomy to achieve healing (n=6) or insertion of a new nail (Grosse and Kempf, n=1) after reaming. There were ten cases of locking screw fracture. Functional outcome was considered good or very good in 89.6% of patients. Twelve patients presented limited dorsal flexion of the foot and nine had pain at the upper end of the nail.

Discussion: Not reaming offers a clear advantage over reaming, particularly for preservation of endosteal vessels. Unreamed nailing is an interesting alternative to external fixation for open fractures. Despite the absence of infection, we do not have any argument in favour of a solid nail to decrease the risk of infection. The time to healing and the rate of true nonunion were not sufficient to clearly favour this method over reamed nailing.

Purpose: Global metatarsus varus is a deformity of the forefoot characterised by medial deviation of all the metatarsals. The condition is often associated with hallux valgus and pes cavus (metatarsus varus sometimes being considered a clinical form of cavus), as well as metatarsal verticalisation predominating on the first ray.

Material and methods: Among twenty patients with metatasus varus in this study fifteen had undergone surgical correction. There were seven men and eight women, mean age 43 years. The deformity was bilateral in most patients (n=10, operated =9) but predominantly on one side in five of them. Metatarsalgia was the common complaint, considered to be global involving the middle rays (n=12 patients), or localised under the head of the first metatarsal (n=3). The calcanean tendon was short in all cases, aggravating subcapital anterior loading. Likewise, 12 of the 15 patients had hallux valgus; mean 45°. For one patient calcaneal osteotomy for valgisation was also performed.

Hallus valgus was corrected whenever present: in three cases an osteotomy was performed alone to raise the first metatarsal followed by a plantar prosthesis. A basal osteotomy of the three middle metatarsals was performed to achieve elevation, valgisation, and shortening: for three cases a Weil osteotomy was performed.

Results: Hallus valgus recurred in all patients who had had correction surgery, with recurrence of metatarsus varus. Basal metatarsal osteotomies healed but after a long period (about six months. Metatarsalgia was unchanged and was situated under the heads that were not perfectly aligned. The Weil osteotomies did not improve the evolution because, like basal osteotomies, they did not prevent recurrence of global metatarsus varus.

Discussion and conclusion: Metatarsus varus is a challenging deformity which responds very poorly to classical treatments of the forefoot. Osteotomy, irrespective of the type, does not prevent recurrence, both for the lateral rays but also for the hallux. Certain authors suggest that metatarsophalangeal arthrodesis could be useful to stabilise the hallux in the corrected position. We have no experience with this method but in light of our results after conservative treatment for joint motion, this would appear to be an interesting option. We have modified our indications in this direction, using a basi-metatarsal osteotomy instead of a Weil osteotomy for the small toes. Lengthening the extensor tendons may be needed.

Purpose: Several techniques have been described for tenotomy of the Achilles tendon. The first method uses an open approach and consisted in classication stairstep tenotomy followed by suture. The second is a percutaneous method using two opposite transverse incisions along the width of the tendon followed by tension to glide the tendon fibres over each other. The biomechanical and histological properties of operated tendons was analysed in an experimental study in the rabbit.

Material and methods: Eighteen New Zealand rabbits were operated on. The operated and control tendons were harvested at the fifteenth and thirtieth day. Their biomechanical properties (resistance, elasticity, deformation) were measured with an Instrom device. Histological examination focused on the tendon junction using standard staining techniques.

Results: The two methods provide excellent technical reproducibility. We did not have any cases with skin problems or infection. Twelve tendons harvested at different times were tested in correct histological and technical conditions. The Instrom fixation system was the only factor limiting this method. Results for the first tendons tested did not demonstrate any difference for maximal force (TC15=118N, TP15=127 N) or for force at rupture (TC15=104N, TC15=114N). Conversely maximal lengthening before rupture (TC15=27mm, TP15=43mm), tendon section (TC15= 35mm2, TP15=27mm2), maximal strength (TC15=3.5mPa, TP15=4.6mPa), percentage of deformation at maximal force (TC15=39%, TP15=28%), fibre strength (TC15=6041 Cm/Denier, TP15=6451 Gm/Denier) and elasticity (TC15=27.7 mPa, TP15=43.7 mPa) were different.

Discussion: Section of the tendons is different with the two techniques. Macroscopically, TP tendons have a regular fusiform aspect which is not found for TC tendons. Maximal resistance and maximal force before rupture were identical for the two cohorts. We consider that if the two tendons have identical cross section, TP tendons would be significantly more resistant. Gliding the tendon fibres over each other is the explanation. Furthermore, gliding is achieved by applying force on the fibres, lengthening occurring at the cost of tearing the least resistant and least elastic fibres. Histologically, the healing process is also different between the two techniques, which has an effect on the final outcome.

Conclusion: The resistant and elastic properties are different between the two techniques of tenotomy. The biomechanical properties are excellent, tendon fibre healing and recruitment being adapted to physiological solicitations. Under these conditions, percutaneous lengthening is an excellent technique due to its reliability, easy execution, and the quality of the fibre healing.

Purpose: The purpose of this study was to analyse mechanical failures involving dismonted osteosynthesis materials implanted to fix pertrochanteric or subtrochanteric fractures with a dynamic hip screw (DHS), a Gamma nail, or a plate nail system (STACA).

Material and methods: Our cohort included 16 patients among a series of 350 patients who had been treated with 240 DHS, 80 Staca nailplates, and 30 Gamma nails between 1996 and 1999. We used the Ender classification for the x-ray analysis and the Cuny criteria which describe the most common causes of dismounted material.

Results: According to the defined criteria, 70/350 osteosynthesis assemblies (20%) were considered insufficient on the immediate postoperative x-rays and eventually dismounted in 16 patients. Two of these patients had major osteopaenia according to the Singh criteria and ten underwent revision because of poor clinical tolerance. These patients had six DHS (3 “swinging” cervical nails, two dismounted plates, and one screw protruding into the joint space). A protruding screw was the problem for the eight Staca nail-plates. Two Gamma nails had a “swinging” screw. These cases of dismounted material were predominantly observed in patients with Ender grade 5, 7 and 8 pertrochanteric fractures.

Discussion: Our analysis of these cases revealed several important factors: 1) the quality of the fracture reduction with restitution of the medial pillar of the per-trochanteric mass; 2) central anchoring in the femoral head essential for stable fixation; 3) superior stability of the DHS in grade 1 and 6 fractures due to the greater projected surface improving hold in cancellous bone. Inversely, for subtrochanteric fractures (grade 7 and 8), centromedulary shaft anchoring with a Gamma nail reduces mechanical stress in varus and thus the risk of “swinging” screws. Finally, the monoblock construct of the Staca nail-plate, which does not have the dynamic potential of the DHS and the Gamma nail, raises a risk of protrusion, particularly in case of “internal rotation” fractures with major metaphyseal comminution (grades 4 and 5). This latter type of fixation is however very effective for simple pertrochanteric fractures with minimal comminution (grades 1 to 3).

Conclusion: Material dismounting results from a series of factors related both to the material used and to the operative technique. We thus reserve the Staca nail-plate for grade 1 to 3 fractures in the Ender classification, the DHS for grades 1 to 6 and the nail-screw fixation for subtrochanteric (grade 7 and 8) fractures.

Purpose: Traffic accidents and high level falls are the principal causes of femur trauma. Fractures generally involve the shaft but the proximal or distal metaphyseal zones may also be involved. Skin opening, vascular injury or associated lesions in multiple injury patients are all reasons for emergency treatment with an external fixator.

Material and methods: We report a retrospective series of 23 cases who were treated with this technique between 1996 and 2000. There were 15 men and seven women, mean age 36 years (17–92) who were traffic accident victims in 17 cases. Fourteen had multiple injuries. The mean Index Severity Score was 28 points. Fractures were located in shaft in 16 cases, the proximal metaphysis in three, and in the supra and intercondylar zone in nine. The Chauchoix and Duparc classification was grade 2 in eight cases, and grade 3 in three cases. The fixation was installed with two or three pins in the lateral position; The knee was bridged in cases with an associated injury to the proximal tibia (floating knee) (two cases) or severe injury to the knee ligaments. Patients were reviewed clinically and radiographically. Bone healing was considered to be achieved when full weight bearing was possible without osteosynthesis contention.

Results: Twenty patients were reviewed. Mean follow-up was 20 months (7–42). Bone healing was achieved in 100% of the cases with a mean delay of 9.4 months (4–32). In three patients 13%) a complementary procedure (cancellous graft or bone marrow graft) was needed to achieve healing, the delay in these patients was 22 months compared with 7.5 months without secondary procedures. One patient developed a callus with a > 10° deviation of the AP view and five permanent flexion greater than 10°. Supra and intercondylar fractures healed at a mean 6.6 months in five cases with a deformed callus. The force moment related to excessive spread of the fixator pins (greater than 20 cm) was not a factor of poor final radiological outcome. Mean knee flexion was greater than 100° in only three cases. These amplitudes were not obtained until the fixator pins were removed. No releasing procedures were needed. Three mobilisations under general anaesthesia were needed.

Discussion: External fixation allows stable and dynamic osteosynthesis of femoral shaft fractures. It is indicated when centromedulary nailling is impossible or for patients with an excessively high risk of infection. The insertion of the pins must be rigorously control (perpendicular to the diaphysis, bicortical insertion, far enough apart). Supra and intracondylar fractures remain difficult to stabilise with external fixations and internal plate fixation may be discussed in grade 2 open fractures. These can give poor functional results despite rapid consolidation. An immediate corticocancellous graft may be indicated when metaphyseal comminution requires stabilisation, mainly on the medial aspect to avoid varisation.

Conclusion: External fixation is an interesting solution for safe fixation of open shaft fractures (grade 2 and 3) or fractures associated with vascular and nerve injury. It would be more indicated for shaft fractures than for supracondylar fractures which are difficult to stabilise, particularly in case of major comminution.

Purpose: Local factors such as poor vascular supply, open fracture, or infection can affect the potential for bone formation after fracture, arthrodesis or distraction. The fundamental principal for the treatment of late healing or nonunion is to supplement the local supply of the elements necessary for bone maturation. Centrifuged bone marrow is known to have a osteogenic effect in the treatment of femoral head necrosis or as a complement to conventional grafts. We examined the effect of bone marrow grafts used with conventional grafts.

Material and methods: This retrospective analysis included 14 cases where centrifuged bone marrow graft was used as complementary treatment for post-traumatic nonunion (10 cases), distraction callus (three cases) or late healing after arthrodesis (one case). Bone marrow (300 ml) was harvested from the posterior iliac crest then centrifuged to isolate the maximum number of nucleated cells and stem cells. The centrifugate (60–80 ml) was injected into the fracture site with a trocar during the same operative time. Cell concentrations (total nucleated cells, stem cells (CFU-GM), fibroblastic colonies) were noted. Patients were followed at regular visits. Bone healing was considered to be acquired when weight-bearing was possible without fixation or immobilisation.

Results: Definitive bone healing was achieved rapidly in two cases. Two patients required a conventional graft of a nonunion to achieve consolidation. For six patients, consolidation could not be achieved (three nonunions and three distraction calluses). Final outcome was good or very good in 57% of the cases. Mean delay to bone healing was 6.5 months. The infectious context had no effect on the method. The mean number of nucleated cells injected was 3.9•109 cells in successful cases and 2.8•109 cells in unsuccessful cases. These concentrations affected outcome.

Discussion: This technique for stimulating bone maturation by supplying bone generating cells is indicated for late healing or recent nonunion. It is less effective for distraction calluses or for very old nonunions. Morbidity and iatrogenic effects are minimal. A rigorous harvesting method is required since the result is highly dependent on the cell concentrations and the number of injected cells. Bone marrow injections after centrifugation should be greater than 85 ml and have a cell concentration around 45•106 cells/ml. The method is less successful for old injuries and in patients with arteritis.

Conclusion: Bone marrow grafts are indicated for the treatment of late healing or recent nonunion. Morbidity is low but a rigorous harvesting method is required. The method should be implemented shortly after the fracture without waiting for potential signs of nonunion.