Operative Treatment of L2-Spared Caudal Regression Syndrome


Absence of distal segments of the spine is known as Caudal Regression Syndrome. Depending upon the severity of the regression, paralysis, loss of sensation and contractures of the lower limbs may occur. In severe cases of Caudal Regression Syndrome the so-called "Buddha-like position" is characteristic. The clinical picture combines a shortened trunk due to the absence of the spine, flexion-rotation-abduction contracture of the hip joints, flexion contracture of the knee joints, often combined with a pterygium, and club feet.

Prosthetic management designed to allow standing and walking often implies treatment of the contractures of the hip and knee joints. Therapy of the contractures is a major problem. Neither a soft tissue release nor a bony reconstruction can guarantee a good long-term result; the likelihood of a recurrence is high. In spite of several subsequent surgical interventions, the result is often unsatisfactory. As a radical solution to these problems, some authors suggest the amputation of the lower limbs. From a functional point of view this method seems reasonable because it allows continuous prosthetic management.

As an alternative to amputation, another method of operative treatment developed by Marquardt' will be described. The purpose of this method is twofold: to preserve the lower limbs and to remove the hip and knee joint contractures by extensive shortening of the femurs and resection of the hips.

Case Report

The patient was born in 1979. The X-ray at 6 months of age shows the typical agenesis of the spine below the second lumbar vertebra. The iliac bones are rotated in the frontal plane. Dysplasia of both acetabulae is present (Fig. 1 ). The trunk is visibly shortened, both hip and knee joints have flexion contractures of 90 degrees, and pes equinus is evident (Fig. 2 ). At 13 months of age the child was fitted with an orthoprosthesis which allowed free standing and walking with the aid of a wheeled walker (Fig. 3 ). By the age of 8, the knee flexion contracture had increased to 110 degrees and the hip flexion contracture to 100 degrees. From functional and cosmetic points of view, further prosthetic management was a major problem. For example, the orthoprosthesis for the contractures was bulky, requiring custom-made trousers. It was thus decided to correct the contractures surgically. Operations were performed similarly in two sessions. Surgery on the right side was in October 1986, and on the left in January 1987 (Fig. 4 ). The proximal part of the femur was resected totally at the level of the lesser trochanter. Following this procedure, the hip joint could be extended to 10 degrees. Subsequently the distal part of the femur and the proximal part of the tibia were resected at the level of the epiphyses. Following this procedure, only 10 degrees of extension was lacking in the knee. The femoral head was separated from the femoral neck at the level of the epiphyseal plate and then attached to the femoral shaft. This procedure was performed in order to close the bony wound and to prevent growth of spurs which might restrict postoperative mobility. Fixation was achieved with a Rush pin inserted proximally. In order to facilitate balance, the pin was bent at the level of the knee joint to accommodate the residual hip flexion contracture. The postoperative course was uncomplicated in both operations. X-rays after 13 and 16 months respectively, show a complete bony consolidation of the osteotomy (Fig. 5 ).

Upon clinical examination in November 1987, almost full extension in both hip joints was demonstrated. Active flexion of the hip was 40 degrees on the left and 35 degrees on the right (Fig. 6 ). Passive hip flexion was 90 degrees bilaterally. Because of the arthrodesis, loss of correction in the knee joints is not expected.

Three months after the second operation, the child was fitted with an orthoprosthesis accommodating the corrections. The trunk was stabilized with a pelvic orthosis. The orthoprosthesis permits wearing ordinary trousers and walking with a wheeled walker (Fig. 7-a , Fig. 7-b ). Because of partial sensation in the lower limbs, sitting is improved in comparison with amputation and with the preoperative situation (Fig. 8 ).


Operative treatment of contractures in the hip and knee joints is a major problem in cases of caudal regression. Conventional operative techniques to preserve the limbs, such as plastic surgery, muscle lengthening and joint capsule division with osteotomy, are associated with a high frequency of recurrence. Other authors predominantly propose knee joint disarticulation or subtrochanteric amputation.2-5 From a functional point of view, such radical measures seem favorable because permanent prosthetic management is then possible. In cases of high level amputations where a pelvic brace is required, however, the weight of the orthosis presents difficulties with handling. Minimal function of the lower limbs which is occasionally present cannot be used for movement and for regulation of balance. Furthermore, the proposed surgical procedures are very mutilating.

Coping with an amputation is difficult for the child and parents, especially in the psychologically critical phase from 3 years of age through puberty. The boy in the case report had severe contractures of the hip and knee joints pre venting orthoprosthetic management. In order to avoid amputation, resection of the proximal part of the femurs in the intertrochanteric region and resection-arthrodesis of the knees were performed. In order to preserve the possibility of active movement in the legs as a function of the partially innervated iliopsoas muscle, the femoral head, including the cartilaginous component was attached to the remaining femoral shaft. It is anticipated that with the stimulus of movement in this region, a sliding surface of scar tissue would be promoted by the presence of cartilage. Formation of overshooting callus from the cartilaginous part attached to the femoral shaft could not be prevented completely.

Clinical examination one year following the operations showed no recurrence of the preoperatively existing hip flexion contractures. From full extension, the active flexion of the hip joint was to 45 degrees on the right and to 35 degrees on the left. Passive flexion was to 90 degrees bilaterally.

Resection-arthrodesis of the knee joints with fixation with a Rush pin provided complete stability in this region. On the basis of the comparatively good mobility of the hip joints and the extension achieved in the knees, the child was fitted with an orthoprosthesis. It is important psychologically that readymade clothes may be worn with the orthoprosthesis.

The possibility of retained hip flexion allows walking with the wheeled walker, not only with the swing-through pattern of gait, but also with a reciprocal gait pattern without using special techniques. Lockable artificial hip joints allow a few determinable degrees of mobility. Partial sensation in the legs eases sitting in comparison with the preoperative situation. The same comfort in sitting would not have been possible after amputations. The operative procedure described above has many advantages in comparison with the knee disarticulation and the subtrochanteric amputation proposed elsewhere. In particular, our procedure facilitates greatly the reintegration of the child into his social surroundings.


As a rule, extreme hip and knee flexion contractures exist in severe cases of Caudal Regression Syndrome, for which therapy is difficult. A new operative technique is illustrated by a case example. Correction is achieved through shortening the proximal femur and resection-arthrodesis of the knee joint.

Clinical results achieved with this method permit the use of an orthoprosthesis with satisfactory hip mobility and sitting comfort.

Orthopaedic Hospital of the University of Heidelberg, Schfierbacher Landstrasse 200 a, D6900 Heidelberg, West Germany


  1. Marquardt E: Surgical Treatment of Extreme Flexion-Abduction Contracture of the Hip Joint and Flexion Contracture of the Knee Joint in Agenesis of Lumbar Spine and Sacrum. Journal of the Association of Children's Prosthetic-Orthotic Clinics 22:28, 1987.
  2. Frantz CH, Aitken GT: Complete Absence of the Lumbar Spine and Sacrum. Journal of Bone and Joint Surgery 49-A: 1531-1540, 1967.
  3. Phillips WA, Cooperman DR, Lindquist TC, et al: Orthopaedic Management of Lumbosacral Agenesis. Journal of Bone and Joint Surgery 64-A: 1282-1294, 1982.
  4. Redhead RG, Vitali M, Trapnell DH: Congenital Absence of the Lumbar Spine. British Medical Journal 3:595-596, 1968.
  5. Russell HE, Aitken GT: Congenital Absence of the Sacrum and Lumbar Vertebrae with Prosthetic Management. Journal of Bone and Joint Surgery 45-A:501-508, 1963.