Reconstruction of the proximal humerus after wide resection of tumors : comparison of three reconstructive options

الملخص EN

Purpose : Assessment of the functional results and complications of three bone reconstructive procedures after resection of primary tumors of the proximal humerus.

Material and Methods: Between 2000 and 2008, 32 patients having primary malignant, aggressive benign or metastatic tumors of the proximal humerous were selected for limb sparing surgery.

Preoperative evaluation included CT chest, MRI.

Limb sparing surgical resection was done including intraarticular or extraarticular wide resection of the tumor.

Bone defect was reconstructed with fusion shoulder using free vascularized fibular graft (FFFG) in 11 patients and pedicled lateral scapular crest graft (PLSCG) in 8 patients and mobile shoulder reconstruction using proximal humerus prosthesis in 13 patients.

Those patients were followed-up at regular interval to detect bone union and complications related to bone flaps or prosthesis.

Functional results were assessed for every patient after one year postoperatively.

Results : The median age of the patients was 21 years and the follow-up period ranged from 19 months to 92 months.

Postoperative resection margins were negative in all cases.

The mean length of the resected humerus was 13cm.

The mean operative time for prosthesis cases was 3.5 hours and that for FVFG was 6.5 hours and was 5 hours for PLSCG cases.

The mean time of bone union proximally and distally for FVFG and PLSCG was 4.2 and 5.5 months accordingly.

At 1 year follow-up, the functional results for the three reconstructive procedures were nearly the same with a mean functional score for FVFG cases was 73%, for PLSCG cases was 68% and was 71% for prosthesis cases.

Hand and elbow functions were preserved in all types of reconstruction.

The range of shoulder abduction and flexion was grossly limited with prosthesis cases while it showed marked improvement with fusion by FVFG and PLSCG.

Complications for prosthesis cases were one case proximal migration and one case posterior sublaxation.

Complications of bone flaps were nonunion of one end in 2 cases of PLSCG and one case of FVFG.

Limb shortening was seen in 32 cases with PLSCG.

Conclusion : Summarizing our experience in this small study, we can state that, limb sparing surgical resection of tumors of the proximal humerus is effective in local tumor control and preserving hand and elbow movements.

MSTS functional score of the limb after reconstruction and shoulder fusion with FVFG or PLSCG is nearly the same as mobile shoulder reconstruction with endoprosthesis.

Shoulder range of movement was grossly limited with prosthesis replacement while a wider range of movement was obtained with shoulder fusion.

Pedicled lateral scapular crest graft is able to bridge defects only up to 12cm whereas the fibula can replace a longer defect.

Selection between those reconstructive options should be individualized and is based on the age, the length of defect, the type of resection, intraarticular or extraarticular, preservation of deltoid and axillary nerve, the prognosis of the tumor.