Chronic pain and disability after pelvic and acetabular fractures--assessment with the Mainz Pain Staging System.

Background: Chronic posttraumatic pelvic pain (PPP) after pelvic ring fractures impacts negatively on quality of life issues. This study aimed to more clearly identify and quantify the problem.

Methods: For this cross-sectional study, patients were examined 52 (median) months after pelvic fractures. The following parameters were measured: pain chronicity (Mainz Pain Staging System [MPSS]), pain intensity (Numeric Rating Scale, 0-10), pelvic fracture outcome scores (Majeed, Pohlemann, and Bürk), pain severity (Chronic Pain Grading Questionnaire), pain-related interference with activities of daily living (Chronic Pain Grading Questionnaire), low back pain-related disability (Oswestry score), neuropathic pain (painDETECT), physical functioning (Short Form-12), and medical comorbidities (Weighted Illness Check List-20). Psychological distress was evaluated for anxiety and depression (Hospital Anxiety and Depression Scale) and mental quality of life (Short Form-12).

Results: Sixty-nine patients had a total of 49 pelvic and 41 acetabular fractures; 70% underwent osteosynthesis. The prevalence of PPP was 64%. Prevalence weighted with the dysfunctional pain chronicity stages MPSS II and III was 48%. Patients with pelvic fracture types (AO classification) A, B, and C had PPP prevalences of 38%, 67%, and 90%, respectively. Pain chronicity stages (MPSS) were moderately to strongly correlated with pelvic pain intensity (r = 0.57), the three pelvic fracture outcome scores (r = -0.78 to -0.90), pain-related interference (r = 0.72), Oswestry score (r = 0.68), nerve injury and neuropathic pain (r = 0.52), reduced physical (r = -0.72) and mental functioning (r = -0.58), trauma-related comorbidity (r = 0.53), anxiety (r = 0.51), and depression (r = 0.67).

Conclusion: This study demonstrated that the intensity and prevalence of PPP are high even some 4 years after injury. The validated instruments MPSS (measuring pain chronicity) and Oswestry disability score proved to be appropriate for classifying outcome after pelvic ring fractures.