Preserved insertions of the semitendinosus and gracilis tendons (STG) in ACL reconstruction: a new surgical technique with preliminary results Ravi K. Gupta, Siddharth Aggarwal, Varun Aggarwal, Sudhir K. Garg and Sachin Kumar ABSTRACT Background A torn anterior cruciate ligament leads to loss of proprioception function normally provided by an intact anterior cruciate ligament. Relying on the hypothesis that preservation of the tibial insertions of the semitendinosus and gracilis tendons (STG), while using a quadrupled STG graft may provide better proprioception function, we describe a new surgical technique that uses a quadrupled STG graft with preserved tibial insertions. Methods The study was a retrospective follow-up analysis of 45 patients with anterior cruciate ligament deficient knees that were reconstructed using a new surgical technique. Functional evaluation was done based on the Lysholm Knee Score. Proprioception was tested with active reproduction of passive position (ARPP) test, single-leg forward-hop (SLHT) test, single- limb standing test (SLST) and threshold for detection of passive motion (TDPP) test. The average duration of follow-up was 40.6 months (range, 33--50 months). Results The mean Lysholm score improved from a preoperative value of 62.4 to 95.2 at final follow-up. Various tests demonstrated that there was significant improvement in the quality of propriocep- tion sensation as compared with the preoperative values. However, the sensation was still inferior in comparison to the normal knee. All patients returned to their preinjury functional levels. There was one rerupture resulting from a second injury in a football player at 3.5 years after the surgery. Conclusions The new surgical technique preserving the tibial insertions of the STG with satisfactory early to mid-term functional results is another option for ACL reconstruction that provides significantly superior proprioception sensation compared with preoperative values. However, whether the quality of proprioception is superior to the one provided by a free graft needs to be established by undertaking further double-blind prospective comparative studies. Keywords anterior cruciate ligament, knee, medial hamstrings INTRODUCTION A rthroscopy assisted anterior cruciate ligament (ACL) reconstruction is a widely accepted procedure for the management of ACL rupture. 1--5 The two most commonly used autogenous grafts are the bone-patellar tendon-bone (BTB) graft, and the quadrupled semitendino- sus-gracilis (STG) tendon construct. 1,6 Although both grafts have been successfully used, there have been concerns of anterior knee pain and weakness of the knee extensor apparatus with BTB graft 7--9 and failure of the STG graft in achieving rigid fixation to bone. 10,11 To partially offset this problem, Kim et al. 12 proposed the preservation of the tibial insertions of the semitendinosus and gracilis tendons, while harvesting the graft with an additional fixation of a double spiked washer on the tibial side. The normal ACL, in addition to providing mechanical stability, also contributes to the proprioception sensation of the knee. Proprioception is the sensory modality that encompasses the sensation of joint position and joint motion. Mechanoreceptors, along with muscle spindles for the joint proprioception, have been found in the cruciate ligaments. 13 Loss of proprioception in a knee with a deficient ACL is well documented. 14,15 Thus, in an ACL deficient knee, in addition to the mechanical stability, the restoration of the proprioception should be one of the important goals of any ACL reconstruction surgery. 16 There are reports in the literature that the mechanosensitive afferent units contained in the tendon and aponeurotic insertions of the muscles have the ability to transmit nociceptive and proprioceptive impulses. 17,18 With this background in mind, we started using a new surgical technique, preserving the insertions of the STG, with the aim of obtaining better functional results, espe- cially in terms of improved proprioception of the knee. MATERIALS AND METHODS The current study is a retrospective analysis of 45 patients (39 men and 6 women) who underwent ACL reconstruction with a new surgical technique at our institute from January 2004 to December 2005. Patients older than 60 years of age, skeletally immature patients, patients with associated posterior cruciate ligament (PCL) injury and patients in 1940-7041 ß 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins Department of Orthopaedics, Government Medical College Hospital, Chandigarh, India Correspondence to: Dr Ravi K Gupta, MBBS, MS, DNB, MNAMS, Department of Orthopaedics, Government Medical College Hospital, Chandigarh, India-160047 Tel: þ 91 98765 21592; fax: þ 91 172 2673244; e-mail: ravikgupta2000@yahoo.com INNOVATIONS IN PRACTICE Volume 21  Number 4  July/August 2010 Current Orthopaedic Practice 409