A standardized rehabilitation protocol following two-stage surgery for nonunion of lateral humeral condyle fracture with cubitus valgus in children: functional and radiographic outcomes

Treating nonunion of the lateral humeral condyle with cubitus valgus deformity in children is challenging. While various surgical strategies exist, the role of a structured, standardized rehabilitation protocol in achieving optimal functional outcomes remains underexplored. This retrospective study aimed to evaluate the clinical and functional results of a two-stage surgical strategy (primary in situ fixation with bone grafting followed by secondary corrective osteotomy) coupled with a standardized, closely monitored rehabilitation protocol for pediatric lateral humeral condyle nonunion with cubitus valgus. A retrospective analysis was conducted on nine pediatric patients with humeral lateral condyle nonunion combined with cubitus valgus deformity who were treated at Honghui Hospital, Xi’an Jiaotong University, from January 2016 to March 2020. All underwent the two-stage surgery. In stage I, we performed debridement of the nonunion site, autologous iliac bone grafting, and in situ fixation using cannulated compression screws. Once bone union was achieved and elbow joint function had recovered, we performed corrective supracondylar medial closing wedge osteotomy to address the cubitus valgus deformity in stage II. The key focus of this study is the detailed, phase-specific rehabilitation protocol implemented after each stage: immobilization followed by graduated active-assisted and active range-of-motion exercises post-Stage I, and progressive resistance training post-Stage II. Elbow range of motion (ROM), carrying angle, and Mayo Elbow Performance Score (MEPS) were recorded and compared between the preoperative period and the final follow-up to evaluate treatment outcomes. All patients were followed up postoperatively, with a mean duration of 45.5 months (range: 30–66 months). The mean time to union after the first-stage surgery for nonunion of lateral condyle fractures was 81.3 days (range: 55–120 days). All osteotomy sites in the second-stage corrective surgery achieved union, with an mean healing time of 51.1 days (range: 45–60 days). The elbow ROM improved significantly from a preoperative mean of 128.0° ± 4.6° to 138.5° ± 5.4° at the final follow-up (P < 0.001). The mean carrying angle of the unaffected side was 5.5° (range: 3°–8°). On the affected side, the carrying angle significantly improved from 31.8° ± 4.7° (range: 25°–42°) preoperatively to 4.0° ± 2.2° (range: 1°–8°) at final follow-up (P < 0.05). The MEPS improved from a preoperative mean of 58.5 ± 6.5 (4 fair, 5 poor) to 96.2 ± 3.4 (7 excellent, 2 good) at final follow-up (P < 0.05), indicating significant functional recovery. No avascular necrosis occurred. Transient hardware irritation occurred in one patient (11.1%). The two-stage surgical approach, when integrated with a standardized, phased rehabilitation protocol, is an effective strategy for managing pediatric lateral humeral condyle nonunion with cubitus valgus, yielding significant functional improvements and reproducible outcomes.