Clinical And Biomechanical Research Of Ligament Repair In The Treatment Of Elbow Stiffness

OBJECTIVESPost-traumatic elbow dysfunction is common in clinical, which is also a difficulty of clinicaltreatment. When surgical treatment is expected to achieve complete relase, it will result in varyingdegrees of elbow soft tissue injuries that could easily lead to post-operative joint instability andaffect the function of upper limb. This study aimed to conclude the clinical effect of elbow collateralligaments repair in treating the elbow dysfuction by retrospection, and provide a safe and effectivemethod for clinical treatment of stiff elbows. Meanwhile, the proposed theory was investigated bybiomechanics in repair of lateral collateral ligament.METHODSFrom January2011to August2012, we retrospectively reviewed60patients who sufferred withsevere elbow stiffness in our tertiary trauma centre. Evaluations such as Mayo Elbow PerformanceScore were based on the patient medical history, surgical records and follow-ups includingfunctional mobility, elbow stability, pain and satisfaction. By using homemade elbow biomechanicaltesting machine, The lateral collateral ligament complex were cut sequencely and forearm valgus,external rotation and axial stresses were applied in different elbow flexion angles. The functions ofdifferent bundles of lateral collateral ligament were revealed by measuring the dislocationdisplacement of elbow joint in different situations.RESULTSWith an average of24-month follow-up, the average extension-flexion range of motion (ROM)was increased from33°preoperatively to125°postoperatively, Mayo elbow performance score was improved from59points preoperatively to93points postoperatively. Most of the patientsmaintained normal elbow stability. There were no significant difference between direct ligamentrepair group and anchor ligament repair group in the outcomes and complications. The poor result ofpatients was associated with severe pain and joint instability. With the sequent cuting of thecollateral ligaments, the lateral rotational displacement of elbow joint were gradually increased (p<0.05), the change was most significant in the elbow flexion of45degrees (p <0.05). The incision ofradial collateral ligment made the most significant lateral rotational displacement in simple bundleof ligaments (compared with lateral ulnar collateral ligament and annular ligament). The incision ofradial collateral ligament with annular ligament caused greater displacement than that of annularligament with lateral collateral ligament. The posterolateral rotary displacement was significantlydifferent before and after applying the axial compressive stress at the flexion of0°and45°respectively (p=0.011, p=0.002).CONCLUSIONSIt was safe and effective to treat severe elbow stiffness by open release, ligament repair andhinged external fixator, it could restore the stability and functional mobility and the outcome wassatisfactory. Biomechanical experiments illustrated the lateral collateral ligament complex as awhole functional system, each bundle plays an important role, in which the RCL was a majorstabilizer in posterolateral rotary instability. So it is suggested that the lateral collateral ligamentcomplex should be repaired or reconstructed during surgery. Postoperative elbow strength trainingwill help to improve the overall stability of the joint. Elbow flexion at45degree could be sensitiveto evaluate the instability in clinic.