Pain-Adapted Full Weight-bearing After Ankle Fracture Surgery

A Multicenter, Pragmatic, Single-Armed Prospective Study

With an annual incidence of 74 ± 32 per 100 000 individuals, ankle fractures in Germany are among the most common fractures in adults (1). Modern surgical 360° treatment approaches, comprising anatomical reduction of all fractures and stabilization of associated ligament injuries, together with the use of locking-plate systems or intramedullary nails, have significantly increased the primary stability of their fixation [review article on this topic accepted by Deutsches Ärzteblatt].

However, postoperative management has remained unchanged despite greater primary stability. Standard care in Germany is still immobilization in a walker boot or cast and non-weight bearing/partial weight-bearing of 20 kg for six to eight weeks. Yet, several studies have demonstrated that neither early weight-bearing (2) nor mobilization (3) increases the complication risk (4, 5).

Evidence currently available is limited since immobilization/mobilization and non-weight-bearing/weight-bearing are usually investigated as separate entities. Thus, no relevant studies have examined the effect of early mobilization combined with weight-bearing. The aim of the present multicenter study was to analyze pain-adapted full weight-bearing and mobilization after ankle fracture surgery.

Methods

This is a multicenter, pragmatic, single-armed prospective study undertaken in accordance with the SPIRIT guidelines and registered in advance with clinicaltrials.gov (#NCT05419154). The study was conducted at three German university hospitals (University Hospital Rostock [UMR], University Hospital Carl Gustav Carus Dresden [UKD], University Hospital Munich [LMU]). All adult patients (≥18 years) who had undergone surgery for an acute, isolated, closed, unilateral ankle fracture were eligible for inclusion. Patients requiring syndesmotic stabilization (syndesmotic screw or suture-button system) were excluded. The intervention comprised pain-adapted full weight-bearing on forearm crutches without immobilization. Patients were enrolled after surgery.

Collected data included demographic characteristics, fracture severity, treatment details, subjective patient satisfaction (PROMs: MOxFQ, EFAS, OMAS, EQ-5D-5L), and complications, as defined by a modified Clavien–Dindo classification system. The primary outcome at three months postoperatively was the complication rate. The study flow diagram is presented in the Figure.

Figure

Study flow diagram

All data points, with the exception of the patient-reported outcome measures (PROMs) followed a normal distribution, so parametric and non-parametric tests were applied for the statistical analysis. Normally distributed data are reported as mean +/- standard deviation, with non-normally distributed data as median (interquartile range).

Results

A total of 128 patients were included in the study (number of ankle fractures treated by surgery/number of included fractures): LMU 04/22–07/24, 282/74; UKD 05/24–03/25, 122/27; UKR 10/22–06/24, 209/27. Their age was 45.7 ± 16.5 years, 53% were female, body mass index (BMI) was 26.5 ± 4.9, and the American Society of Anesthesiologists (ASA) score was 1.7 ± 0.6. A uni-, bi-, or trimalleolar ankle fracture was diagnosed in 47.7%, 27.3%, and 25.0% of cases, respectively. Based on the AO classification system, 3.9%, 88.3%, and 7.9% of the fractures were AO 44-A, B, and C fractures, respectively. Three months after surgery, X-rays confirmed bony consolidation of 100% of the fractures with no evidence of secondary displacement.

The LMU cohort was younger than the UKD cohort (41 ± 14 vs. 53 ± 19 years), and its mean BMI was three points less than that of the UKD and UMR cohorts. ASA classification, sex distribution, fracture severity (uni-/bi-/trimalleolar, AO classification) showed no significant differences.

Based on the strict Clavien-Dindo classification system, 21.9% (95% confidence interval: [5.1%; 38.6%]) of the patients developed a complication: Grade I 5.5%, IIA 1.6%, IIB 10.9%; IIIA 1.6%, IIIB 1.6%, IVB 0.8%. That corresponds to a minor/major complication rate of (17.9% [3.5; 32.4])/(4.0% [0.2%; 7.6%]). Examples of major complications include secondary diastasis of the distal tibiofibular joint and abnormal wound healing requiring revision. There were no differences in complication rates across the study centers or with respect to fracture severity.

Three months after surgery, there were still moderate, clinically meaningful differences in patient-reported satisfaction compared with the situation before the injury (Table). However, the PROM scores had already achieved moderate-to-good results. Across the study centers, only the MOxFQ social interaction domain showed better, albeit not clinically relevant, preoperative values in the UKD cohort.

Table

Subjective patient satisfaction (PROMs) before accident (preOP) and 3 months after surgery (3mos PostOP)

Discussion

In this multicenter study involving 128 patients, the combination of early weight-bearing and mobilization after ankle fracture surgery did not result in an increase in complication rate.

The major complication rate of 4.0% observed in the present study is in line with the rates of 0 to 8% reported in the literature (2, 5). The mildly higher minor complication rate (17.9% versus 7 to 16% in the literature) is most likely attributable to the Clavien-Dindo classification system used here, with its markedly lower threshold (classification bias) (2, 5). Overall, this study confirms that the combination of early weight-bearing and mobilization does not result in an increased complication rate.

Functional results, even after three months, also demonstrate moderate-to-good outcomes. The OMAS scores reported here were at least comparable to those of studies with a short follow-up (<6 months) and restrictive postoperative management (2, 4). Twelve-month results are not yet fully available and will be reported in a later manuscript.

The main limitation of the present study was the absence of a control group. Furthermore, enrolment and PROM data collection were conducted after surgery and therefore represented a possible selection/recall bias. The decision to stabilize the syndesmosis, however, could only be made intraoperatively.

The strengths of the study are its multicenter design, its case numbers, the systematic collection of complication data, and the use of validated questionnaires. Future studies should include a study arm with restrictive postoperative management, for example, 20 kg partial weight-bearing for six weeks.

Sebastian Felix Baumbach, Thomas Mittlmeier, Dagmar-C. Fischer, Wolfgang Böcker, Stefan Rammelt, Hans Polzer

OrthoPlus, Munich (Baumbach, Polzer), [e-mail]

Department of Orthopedics and Trauma Surgery, Musculoskeletal University Center Munich (MUM), LMU University Hospital, LMU Munich (Baumbach, Böcker, Polzer)

Department of Trauma, Hand and Reconstructive Surgery, University Hospital Rostock (Mittlmeier, Fischer)

University Center for Orthopedic, Trauma and Plastic Surgery, University Hospital Carl Gustav Carus, TU Dresden (Rammelt)

Conflict of interest statement
The authors declare that no conflict of interest exists.

Manuscript received on 4 November 2025, revised version accepted on 19 February 2026.

Translated from the original German by Dr. Grahame Larkin.

Cite this as:
Baumbach SF, Mittlmeier T, Fischer DC, Böcker W, Rammelt S, Polzer H: Pain-adapted full weight-bearing after ankle fracture surgery: A multicenter, pragmatic, single-armed prospective study. Dtsch Arztebl Int 2026; 123: 250–1. DOI: 10.3238/arztebl.m2026.0029

References

1. Milstrey A, Baumbach SF, Pfleiderer A, et al.: Trends of incidence and treatment strategies for operatively treated distal fibula fractures from 2005 to 2019: A nationwide register analysis. Arch Orthop Trauma Surg 2022; 142: 3771–7

2. Bretherton CP, Achten J, Jogarah V, et al.: Early versus delayed weight-bearing following operatively treated ankle fracture (WAX): A non-­inferiority, multicentre, randomised controlled trial. Lancet 2024; 403: 2787–97

3. Matthews PA, Scammell BE, Coughlin TA, Nightingale J, Ollivere BJ: ­Early Motion and Directed Exercise (EMADE) following ankle fracture ­fixation: A pragmatic randomized controlled trial. Bone Joint J 2024; 106-B: 949–56

4. Lewis SR, Pritchard MW, Parker R, et al.: Rehabilitation for ankle ­fractures in adults. Cochrane Database Syst Rev 2024; 9: CD005595

5. Baumbach SF, Rellensmann K, Spindler FT, et al.: Immediate weight ­bearing without immobilization for operatively treated ankle fractures is safe—A systematic review. Foot Ankle Surg 2023; 29: 306–16