Surgical Lengthening of the Very Short Humeral-Amputation Stump

James M. Hunter, M.D. James E. Sweigart, C.P.O. Frederick L. Cole, Jr., DO.

In 1968 two of the authors (Hunter and Sweigart) reported their experience with surgical lengthening of the very short humeral-amputation stump and with subsequent effects on prosthetic fitting. At that time a case was presented with a six-month follow-up1. Staged surgical lengthening was performed in August 1967 at the Elizabethtown Hospital for Children and Youth, Elizabethtown, Pennsylvania, and the patient has now been followed for approximately 7 and 1/2 years. His postoperative course will be reviewed, and our experience with postoperative prosthetic fitting will be discussed.

Patients with very short humeral-amputation stumps and patients with bilateral amelia often have been treated with conventional shoulder-disarticulation prostheses. As the amputation site approaches the level of the humeral neck, instability of the prosthesis may limit terminal-device function to such a degree that the prosthesis is discarded. Although externally powered prostheses have yielded encouraging results, they have not been completely problem-free. Arthrodesis of the shoulder has been used to harness scapulohumeral motion for the flail above-elbow amputation stump. Swanson2 described a case in 1967 utilizing a flbular graft to lengthen a short humeral-amputation stump surgically.

In 1967 we were faced with a difficult problem. A 12-year-old boy, who had sustained a traumatic amputation through the proximal humerus, was being followed in our Upper Extremity Amputee Clinic. The initial injury occurred when the patient was 5 and 1/2 years of age (Fig. 1 ). Although the amputation stump was short, the patient maintained good muscle control of his shoulder girdle. He was fitted initially with a double-walled humeral-neck prosthesis with a positive-locking elbow and a shoulder saddle with chest-strap harness. The patient later underwent refitting and was given an elbow-lift assist. Despite this addition and multiple socket adjustments, the patient continued to have difficulty and was limited by his shoulder-socket instability.

In 1967 staged surgical lengthening was begun. A tube pedicle was prepared from the chest wall. One month later a 6-cm, full-thickness, fibular bone graft was placed in this tubular extension of the stump to lengthen the lever arm of the humerus. Our short-term follow-up was reported previously1.

Six weeks following his discharge from the hospital, the patient was thrown to the floor while wrestling with his brother and sustained a blow to the tip of his augmented humeral stump. X-rays were taken when he was evaluated at the hospital and showed a fracture through the distal 2.5-em portion of the flbular graft. The tip of the fibular graft never reunited to the remaining shaft, and this injury contributed to the eventual shortness of the final stump.

At the present time, the patient is an active 19-year-old male with only minor prosthetic fitting problems involving normal repairs due to prosthetic use and socket revisions necessitated by growth. He is fitted with an above-elbow prosthesis and is an excellent prosthetic wearer. He is active in competitive athletics and presently is enrolled in college. He maintains good motion in the right shoulder (Fig. 2-A , Fig. 2-B , and Fig. 2-C ; and Table 1 ). We have continued to observe the fibular graft in the humeral stump since surgery. Except for the 2.5-cm distal segment which was fractured shortly after the patient's discharge from the hospital, the roentgenographic appearance of the fibular graft has remained stable. The graft showed partial resorption and became conical in appearance during the first year following surgery. However, the roentgenographic appearance of the fibular graft has shown no progression of this resorptive process since 1969 (Fig. 3-A , Fig. 3-B , and Fig. 3-C ).

The patient was interviewed in February 1975. At that time he felt that although the tip of his augmented stump was no longer as firm as it had been originally, he still had good prosthetic stability. He has had minimal prosthetic repairs. He still feels quite satisfied with the results of his surgery.

The use of a staged lengthening of the humerus by pedicle skin graft and fibular bone graft has produced satisfactory stump-socket stability and a satisfied patient in this case. The increased stability has contributed to improved prosthetic function through a full range of elbow motion. We feel that the staged stump-lengthening procedure has been very helpful to this patient. The procedure has enabled us to upgrade this patient's amputation functionally from a shoulder-disarticulatiofl to an above-elbow amputation. We also feel, based on our experience with this short humeral stump, that this procedure may be applicable in the patient with a very short below-elbow amputation. We have not, however, found a suitable patient for this latter procedure. We feel today, as we felt in 1968, that staged surgical lengthening should be considered in the well-motivated, high-humeral amputee.

Elizabethtown Hospital for Children and Youth, Elizabethtown, Pennsylvania

1. Hunter, James M., and Mohaveer P. Probhakar, Surgical lengthening of the very short humeral amputation stump. Inter-Clin. Inform. Bull., 8:2:6-14, November 1968.
2. Swanson, Alfred B., Phocomelia and congenital limb malformations, reconstruction and prosthetic replacement. Am. J. Surg., 109:298, March 1968.