Is McMurray's osteotomy obsolete?PM Phaltankar, K Bhavnani, S Kale, S Sejale, BR Patel
Department of Orthopaedics, KEM Hospital, Parel, Mumbai.
A review of the method of performing, advantages, disadvantages of McMurray's displacement osteotomy with regard to treatment of nonunion of transcervical fracture neck femur with viable femoral head was carried out in this study of ten cases, in view of the abandonment of the procedure in favour of angulation osteotomy. Good results obtained in the series attest to the usefulness of McMurray's osteotomy in the difficult problem of nonunion of transcervical fracture neck femur in well selected cases with certain advantages over the angulation osteotomy due to the 'Armchair effect'.
Keywords: Adult, Female, Femoral Neck Fractures, radiography,surgery,Fracture Fixation, Internal, Human, Male, Osteotomy, methods,Reoperation, Treatment Outcome,
A study of the usefulness of McMurray's osteotomy described by TP McMurray in 1936 in treating non-union of Trans-cervical fracture neck femur was undertaken to counter the scepticism and lack of knowledge about the procedure in the new generation of orthopaedicians. This attitude is not surprising as the newer editions of standard textbooks mention the procedure only briefly. In this series, we have treated ten cases of non-union of Trans-cervical fracture neck femur with a viable head by the displacement osteotomy and assessed the functional results.
A brief review of the method of McMurray's displacement osteotomy in non-union Trans-cervical fracture neck femur follows.
Preoperatively traction is applied to the limb to pull the distal fragment inferiorly, if there is severe overriding. The osteotomy starts below the level of lesser trochanter and proceeds in an oblique manner to exit proximal to the lesser trochanter medially. Obliqueness of the osteotomy facilitates displacement. It is important that the osteotomy exits above the lesser trochanter so that the distal fragment can be made to, come in direct contact with the fracture site and the inward pull of the psoas major inserted into lesser trochanter helps in maintaining the displacement.
The lower fragment is displaced medially by manual pressure and abduction so that it is placed under the head of the femur. Recent advocation is not to displace the shaft more than 50% of the width so as to minimise the deformation of proximal femoral anatomy in view of the possibility of future total hip joint replacement.
The fracture can be fixed with maintenance of the displacement at osteotomy site by using implants such as cancellous screws or Smith-Peterson nail in conjunction with Tupman plate. The displacement at the osteotomy site only can be maintained with a Wainwright splint or no implants may be used relying on 1 ˝ hip spica cast for immobilisation in cases where hip spica cast is used. The extremity which is abducted maximally initially to maintain displacement is adducted to 30 degree of abduction at the end of 3 weeks.
We studied 10 cases of established non-union of Trans-cervical fracture neck femur with viable femoral head treated with McMurray's displacement osteotomy. M: F ration was 7A. Age of the patients varied from 25 years to 45 years. Six patients had been operated previously with implant failure. The rest (four) were untreated cases in which non-union had resulted. Period of non-union ranged from 3 months to 1 year. In 7 patients the femoral neck was completely or almost completely absorbed as noted on preoperative X-rays.
Femoral head vascularity was ascertained by preoperative bone scan studies and was a prerequisite for performing the osteotomy. In all cases, the fracture was fixed internally with either cancellous screws or Smith-Peterson nail. In six cases the displacement of the osteotomy was maintained using a Tupman plate. The rest were immobilised in ˝ hip spica cast.
The results were assessed clinically and radio-logically 6 months to 1 year after the surgery,
The factors for assessing the result included hip function knee function, degree of shortening, amount of residual pain and discomfort & union of the un-united fracture.
1. Hip function: All but two had at least 90 degree flexion- greatest was 110 degree. Two cases considered as failures had upto 60 degree of flexion with restricted abduction & rotations. At rest, abduction averaged from 20 to 45 degree with approximately 30 degree of rotation.
2. Knee function: Found to be good in all cases.
3. Degree of shortening: Maximum was 1.2W
4. Amount of residual pain and discomfort: Considerable pain and discomfort with a lurch was present in the two tailed cases. Among the rest, 3 patients had minimal pain and lurch which disappeared over a period of 3 months.
5. Union of non-united fracture: Fracture remained non-united in 3 cases. Union was questionable in 2 cases. Union was observed in 5 cases, Hence 8 out of 10 patients had a good result in terms of satisfactory motion in hip & knee with minimum shortening and ability to return to former occupation, though only 5 out of these showed union of the fracture while in 2 the union was questionable and 3 had persistent non-union.
Following were the two failures:
1. Internal fixation with Smith Per-terson nail and 2 Tupman plate. Patient was sent home in Thomas traction came with implant failure with cut not of S. P. pin and failure of maintenance of displacement of the osteotomy and non-union after apparently having borne weight on the limb.
2. Osteotomy united in a well displaced position, fracture remaining un-united. The patient had considerable pain and discomfort with lurch and restricted hip motion.
McMurray's displacement osteotomy is effective in treating non-union of Trans-cervical fracture neck femur in the following 2 ways.
1. By making the fracture line more horizontal hence converting shearing forces to compressive, forces it promotes union across the fracture site. The valgus lifting of the proximal fragment occurs due to the pull of the psoas major on the distal fragment through lesser trochanter which rotates the femoral head upwards. Also while reducing the abduction at 3 weeks post-op the proximal fragment is rotated into valgus as it moves with the distal fragment.
2. 'Arm chair effect'. Since the distal fragment is placed directly under the head of femur, weight transmission occurs from the head to the distal shaft fragment bypassing the fracture site. Hence even it the fracture does not unite, painless weight bearing is possible.
Thus, McMurray's osteotomy allows painless weight bearing even in presence of persistent non-union which is a marked advantage over angulation osteotomy considering the refractory nature of non-union of Trans-cervical fracture neck femur.
Distortion of proximal femoral anatomy compromising future THR is an often stated disadvantage but since the osteotomy is done in presence of preserved vascularity of femoral head, collapse and secondary osteoarthritis requiring total hip replacement is uncommon. Thus, we find McMurray's displacement osteotomy as a useful alternative for treating young patients with non-union Trans-cervical fracture neck femur with vascular femoral heads and markedly absorbed neck where union may be improbable if not impossible.
[Figure - 1], [Figure - 2]