Patient-reported Outcomes and Muscle Strength after a Physiotherapy-led Exercise and Support Brace Intervention in Patients with Acute Injury of the Posterior Cruciate Ligament: A Two-year Follow-up Study

Randi Gram Rasmussen; Julie Sandell Jacobsen; Birgitte Blaabjerg; Torsten Grønbæk Nielsen; Lene Lindberg Miller; Martin Lind

doi:10.26603/001c.83214

Patient-reported Outcomes and Muscle Strength after a Physiotherapy-led Exercise and Support Brace Intervention in Patients with Acute Injury of the Posterior Cruciate Ligament: A Two-year Follow-up Study

Int J Sports Phys Ther. 2023 Aug 2;18(4):807-819. doi: 10.26603/001c.83214. eCollection 2023.

Authors

Randi Gram Rasmussen¹, Julie Sandell Jacobsen², Birgitte Blaabjerg¹, Torsten Grønbæk Nielsen³, Lene Lindberg Miller¹, Martin Lind³

Affiliations

¹ Department of Physiotherapy and Occupational Therapy Aarhus University Hospital.
² Research Centre for Health and Welfare Technology, Programme for Rehabilitation VIA University College.
³ Department of Orthopaedic Surgery, Division of Sportstraumatology Aarhus University Hospital.

Abstract

Background: While outcomes of posterior cruciate ligament (PCL) injuries treated surgically are well described, prospective studies reporting outcomes of exercise interventions are lacking.

Purpose: The purpose of this study was to investigate changes in patient-reported outcomes of a physiotherapy-led exercise and support brace intervention in patients with acute injury of the PCL over a two-year follow-up period. Furthermore, this study sought to investigate changes in isometric knee muscle strength over an eight-month follow-up period, and finally to report conversion to surgical reconstruction over a two-year follow-up period.

Study design: Case series study, prospective.

Methods: Fifty patients with an acute injury of the PCL were treated with a brace and a physiotherapy-led exercise intervention and followed prospectively. Changes in patient-reported outcomes were measured with the International Knee Documentation Committee Subjective Knee Form (IKDC-SKF) and the Knee injury and Osteoarthritis Outcome Score (KOOS) from baseline (diagnosis) to two-year follow-up. Furthermore, changes in isometric knee flexion and extension strength were measured with a static strength dynamometer from 16 weeks after diagnosis to one-year follow-up. Conversion to surgery was prospectively extracted from medical records. Mean changes were analyzed with a mixed effects model with time as a fixed factor.

Results: The IKDC-SKF score improved 28 (95%CI 24-33) IKDC points from baseline to two-year follow-up. Isometric knee flexion strength of the injured knee increased 0.18 (95%CI 0.11-0.25) Nm/kg from 16 weeks after diagnosis to one-year follow-up, corresponding to an increase of 16%. In contrast, isometric knee extension strength of the injured knee did not change (0.12 (95%CI 0.00-0.24) Nm/kg, p=0.042). Over two years, seven patients converted to PCL surgical reconstruction. One and two-year follow-up were completed by 46 and 31 patients, respectively.

Conclusions: The physiotherapy-led exercise and support brace intervention demonstrated clinically relevant improvements in patient-reported outcomes and knee flexion strength, and the risk of PCL surgical reconstruction was considered low within the first two years.

Keywords: Isometric knee strength; Non-operative treatment; Physiotherapy; Progressive exercises; Self-reported outcome.