Session VI - Upper Extremity

Functional Outcome of Percutaneous Pinning of Three- and Four-Part Proximal Humeral Fractures

Clifford B. Jones, MD¹; James R. Ringler, MD¹; Karl C. Roberts, MD²; Timothy Elzinga, MS¹;

¹Spectrum Health Medical Center, Grand Rapids, Michigan, USA;

²Grand Rapids Orthopaedic Residency Program, Grand Rapids, Michigan, USA

Purpose: We evaluated the results of percutaneous pinning of three- and four-part proximal humeral fractures.

Methods: During a 2-year period, 19 patients with unstable displaced three- and four-part proximal humeral fractures were identified. The injury and postoperative radiographs were classified according to the AO/OTA classification and reviewed by four orthopedists. All fractures were treated with use of the same protocol. Closed reduction, joystick maneuvers, and percutaneous reduction were used in all patients, and 2.5-mm terminally threaded Schantz pins were percutaneously inserted. Forward flexion was initiated immediately after surgery. At 7 weeks, all pins were removed and unlimited range of motion was initiated. All patients had SF36 and MFA evaluations.

Results: The average age of the patients was 72 years (range, 52 to 92), and there were 14 women and 5 men. The dominant extremity was injured in 18 of the 19 patients. The average follow-up was 33 months (range, 24 to 49). With use of the Neer classification system, 15 fractures were three-part and 4 fractures were four-part. With the AO classification, fractures were classified as 11B2.2 (8), 11B2.3 (4), and 11C2.2 (7). No dislocations were noted. The average length of surgery was 53 minutes (range, 45 to 125). The average number of 2.5-mm Schantz pins inserted was seven (range, 6 to 9). The average postoperative Abd/FF range of motion was 139° (range, 90° to 180°). The following complications were recorded: avascular necrosis (N = 2), reflex sympathetic dystrophy (N = 1), and physical therapy-induced fixation impaction (N = 1). No infections or migrating pins were noted. SF-36 (P = 0.0036) and MFA (P = 0.000048) scores improved with time. The biggest step in improvement occurred between the 12- and 24-month measurements. The arm/hand function improved at each interval from 8, to 12, to 33 at the 6-, 12-, and 24-month intervals, respectively. The 24-month UCLA shoulder score was 25 (range, 17 to 34).

Conclusion: Displaced unstable proximal humeral fractures are difficult to treat and to obtain a good result. Geriatric bone in the proximal humeral metaphysis and head provides poor implant purchase. Percutaneous pinning avoids soft tissue and vascular disruption. The technique requires attention to detail with parallel or divergent terminally threaded pins that are manually tightened, not drill inserted or tightened. The shaft-head pins (N = 4) require neutralization with pins (N = 2 to 4) inserted 90° to these. "Pin-walking" allows for percutaneous tuberosity reduction. Strict adherence to postoperative physical therapy will reduce patient pain and pin loosening. When compared with standard hemiarthroplasty results, percutaneous pinning saves patients' bone, restores pre-injury range of motion, and results in good functional outcome scores. Patients should continue to improve with time. The UCLA shoulder score did not seem to correlate with the SF-36 and MFA scores.

Significance: Patients with proximal humeral fractures treated with percutaneous pin fixation should continue to improve with time. Despite osteopenic bone quality, percutaneous pin fixation of proximal humeral fractures functions very well.