Hamstring Tendon Harvest Research Articles

Relationships Among Tendon Regeneration on MRI, Flexor Strength, and Functional Performance After Anterior Cruciate Ligament Reconstruction With Hamstring Autograft

Background: There are numerous reports on hamstring tendon regeneration after harvest for anterior cruciate ligament (ACL) reconstruction. However, few studies have evaluated the relationships among the magnetic resonance imaging (MRI) findings of hamstring regeneration, muscle strength, and functional results. Purpose: This study evaluates the correlations among the hamstring regeneration on MRI, flexor strength, and functional performance after hamstring tendon harvesting in ACL reconstruction. Study Design: Cohort study; Level of evidence, 3. Methods: We enrolled 45 patients who underwent primary ACL reconstruction using hamstring tendon autografts and in whom flexor strength, functional performance, and preoperative and postoperative MRI results were evaluated at least 2 years postoperatively. Isokinetic flexion strength was tested in the standard and prone positions. We evaluated the differences in flexor strength and functional performance according to the number of regenerated tendons. The correlation between the MRI findings (the number of regenerated hamstring tendons and proximal shift of the musculotendinous junction) and the functional performance and flexor strength was analyzed. Results: The patients were divided into 3 groups according to the regeneration of the hamstring tendons on MRI: both semitendinosus and gracilis tendons regenerated (group SG), only 1 tendon regenerated (group O), and no tendon regenerated (group N). Significant differences were found in the flexor deficit between group N and groups SG and O on the standard and prone position isokinetic tests. There was a significant correlation (ρ = –.472) between the number of regenerated hamstring tendons and the carioca test result. The proximal shift significantly correlated with the flexor deficit in the prone position isokinetic test (semitendinosus, r = .449; gracilis, r = .366). Conclusion: Hamstring tendons regenerated after harvest for ACL reconstruction in a high proportion of the patients. The flexor strength with both the standard and prone position isokinetic tests differed in the 3 groups. The number of regenerated hamstring tendons was significantly correlated with performance on the carioca test. Proximal shifting of the musculotendinous junction was significantly correlated with flexor deficit on the hyperflexion isokinetic test.

Hamstring Strength Recovery is Similar Regardless of which Hamstring Tendons are Harvested for ACL Reconstruction

Concerns have been raised regarding the influence of hamstring tendon harvest on post-operative knee flexor strength after anterior cruciate ligament (ACL) reconstruction. There is some evidence that harvesting both the semitendinosus and gracilis tendons may lead to greater strength deficits in deep knee flexion when compared to harvesting the semitendinosus alone. PURPOSE: To evaluate the influence of single compared to multiple hamstring tendon harvest on knee flexor strength for patients who had returned to sport following ACL reconstruction surgery. METHODS: Fifty participants were included in the study. They had all returned to regular sporting activity a mean 32.5 months after ACL reconstruction with a four-strand hamstring tendon graft. Patients had either semitendinosus and gracilis (ST/G; n = 30) harvested or semitendinosus alone (ST; n = 20). Isokinetic and isometric hamstring strength were measured, and the standing knee flexion angle used to evaluate functional hamstring strength recovery. RESULTS: No significant differences between the groups were found for any of the strength measures or the standing knee flexion angle. A consistent deficit of between 8 and 22% was observed in the strength of the operated limb when compared to the non-operated, regardless of which tendons were harvested. No relationship was found between the standing knee flexion angle and the isometric hamstring strength results obtained at 105° knee flexion (r2 = 0.034). CONCLUSIONS: The choice between one or two hamstring tendons is unlikely to significantly influence post-operative hamstring strength outcomes in people returning to sport, as both graft options were shown to have similar strength outcomes at two years post-operatively. Persistent hamstring strength deficits in the operated limb compared to the non-operated limb were found which may have implications for post-operative athletic performance. However the functional significance of these deficits is at present unclear. The results also demonstrate the standing knee flexion angle should not be used as a surrogate clinical measure of hamstring strength as it correlated poorly with dynamometric measures of hamstring strength.

Posterior Mini-incision Hamstring Harvest

Many orthopedists looking for alternatives to autograft bone-patellar-tendon-bone grafts are uncertain of their ability to harvest a hamstring graft of adequate length. They may use an allograft instead for this reason despite recent reports of high failure rates. This article presents step-by-step instructions for a posterior mini-incision hamstring harvest that offers a safe and simple method of reliably harvesting sufficient hamstring for 4 or 6 strand repair, while using tiny incisions for excellent cosmesis and minimal pain. Access from the posterior mini-incision allows easy identification and differentiation of the semitendinosus and gracilis (Gr) tendons, as well as precise placement of the anterior mini-incision for tibial tunnel drilling and fixation. Most importantly sectioning of the intertendinous cross-connections is performed under easy direct vision posteriorly, instead of at a distance from the typical anterior incision under retractors. This prevents the tendons from being cut too short by the tendon stripper and is particularly useful in large patients. In addition to the surgical procedure, details on the required equipment are presented.

Hamstring tendon harvesting — Effect of harvester on tendon characteristics and soft tissue disruption; cadaver study

The purpose of this study was to determine whether the type of hamstring tendon harvester used can influence harvested tendon characteristics and soft tissue disruption. We compared two different types of tendon harvesters with regard to the length of tendon obtained and soft tissue disruption during hamstring tendon harvesting. Thirty six semitendinosus and gracilis tendons were harvested using either a closed stripper or a blade harvester in 18 paired knees from nine human fresh cadavers. Use of the blade harvester gave longer lengths of usable tendon whilst minimising the stripping of muscle and of any non-usable tendon. Our results suggest that the type of harvester per se can influence the length of tendon harvested as well as soft tissue disruption. Requesting such data from the industry prior to deciding which harvester to use seems desirable.

18 Knee flexor strength is compromised at deep knee flexion angles after hamstring tendon harvest for ACL reconstruction

18 Knee flexor strength is compromised at deep knee flexion angles after hamstring tendon harvest for ACL reconstruction

Prevalence of Saphenous Nerve Injury After Autogenous Hamstring Harvest: An Anatomic and Clinical Study of Sartorial Branch Injury

Injury to the sartorial (terminal) branch of the saphenous nerve (SBSN) has received little attention in the literature, despite its anatomic proximity to the hamstring tendons during autogenous harvesting. This study aims to define the prevalence of saphenous nerve injury after anterior cruciate ligament (ACL) reconstruction with autogenous hamstrings and define clinically relevant anatomy that may contribute to nerve injury. Surveys regarding the presence and duration of sensory changes in the infrapatellar branch of the saphenous nerve (IPBSN) and SBSN were retrospectively sent to 164 patients who had undergone arthroscopically assisted ACL reconstruction with hamstring autograft over a 4-year period. Eleven cadavers were then dissected to identify the relation of the saphenous nerve to the hamstring tendons and accessory insertions. Postoperative sensory disturbance was present in 74% of patients surveyed. Concomitant injuries to both the SBSN and IPBSN occurred in 32% of patients, whereas isolated paresthesias in the SBSN and IPBSN distribution affected 23% and 19%, respectively. The saphenous nerve was intimately associated with the gracilis for 4.6 cm in the distal thigh, from 7.2 cm (range, 6.4 to 9.3 cm) to 11.8 cm (range, 7 to 13.2 cm) proximal to its insertion. Accessory hamstring insertions were present distal to the point where the sartorial branch became extrafascial. The SBSN is at higher risk of injury during hamstring ACL reconstruction than has been previously reported. The saphenous nerve is intimately involved with the gracilis tendon for a portion of its course in the distal thigh, likely predisposing it to damage during passage of the tendon stripper. Level IV.

Hip extension strength following hamstring tendon harvest for ACL reconstruction

Hamstring autograft harvest for ACL reconstruction may have an effect on hip extension strength and this may be important especially in sports that involve high speed running such as soccer, rugby, American football and the sprint disciplines of track and field. This aspect of hamstring tendon harvesting has not been looked at before. We have performed a non-randomised prospective case control study comparing isokinetic hip extension strength following four strand semitendinosus and gracilis tendons (4SHS) and bone-patellar tendon-bone (BPTB) autografts in ACL reconstruction. Isokinetic hip extension was assessed at 3 and 12 months post-operatively using a Kin-Com machine at a speed of 30° per second. Three months post-operatively there was a significant decrease ( p < 0.05) in the peak force of concentric hip extension in the 4SHS group. There was no evidence that hip extension is weaker following ACL reconstruction with 4SHS tendon autograft than ACL reconstruction with BPTB autograft at 12 months post-operatively. We find no contra-indication to the use of 4SHS tendon autografts in ACL reconstruction in patients who wish to preserve hip extension strength for their sporting activities.

Erratum

The article “Influence of Medial Hamstring Tendon Harvest on Knee Flexor Strength after Anterior Cruciate Ligament Reconstruction” by Tashiro et al, published in the April 2003 issue (pages 522–529), contains an error. The fourth author's name is Atsuhiko Hikita. The corrected version of the article appears online for journal subscribers at http://ajs.sagepub.com/cgi/reprint/31/4/522.

In-Vitro Study of Hamstring Graft Morphometry and an Intraoperative Technique to Avoid Premature Amputation when Harvesting the Graft for ACL Reconstruction (SS-54)

Autograft hamstring harvest continues to be one of the most technically demanding aspects of arthroscopically-assisted ACL reconstruction [1Allum R. JBJS Br. 2003; Google Scholar]. The fascial attachments between the semitendinosus and gracilis and from the semitendinosus to the medial head of the gastrocnemius have been previously described as threats to premature amputation [2Solman Jr, C.G. Orthop Clin North Am. 2003; PubMed Google Scholar]. The fascial bands are believed to become continuous with the posterior crural fascia eight to 10 cm from the pes anserine insertion [2Solman Jr, C.G. Orthop Clin North Am. 2003; PubMed Google Scholar]. An in vitro study [3Ferrari J.D. Orthop Rev. 1991; PubMed Google Scholar] found that the mean distance from the semitendinosus insertion to the tendinous reflection of its fascial connection was 7 cm. These prior efforts, however, did not quantify the extent of this fascial attachment to the semitendinosus. Additionally similar fascial attachments to the gracilis and the anatomical morphometry of the sartorius fascial band have yet to be described. The objectives of this study were to describe: (1) the anatomic morphometry of the sartorius, gracilis and semitendinosus fascia band attachments in a cadaver model; (2) an intraoperative technique to assess the level of dissection of these attachments. Knowledge of these fascial connections is crucial to avoid premature amputation during autologous hamstring harvest for ACL reconstruction. Seven fresh-frozen cadaveric lower limbs from five female donors (average age 64 years) were used. The medial side of the knee was exposed and the sartorius fascia incised. The gracilis and semitendinosus tendons were released distally from the tibia. A 1.1mm K-wire, drilled into the tibia at the medial edge of the patella tendon, marked the center of this insertion site. The gastrocnemius fascia band attachments to the sartorius (SFB), gracilis (GFB) and semitendinosus (STFB) were identified. Five measurements were independently made by three examiners: SFB width, GFB width, STFB width, wire to distal edge of GFB, and wire to distal edge of STFB. The sartorius (SFB) and semitendinosus fascia bands (STFB) were created by firmly adherent fascia overlying the medial head of the gastrocnemius. The gracilis fascial band (GFB) acted as a sling formed by the sartorius fascial band (SFB) and gastrocnemius fascia attachments. The average distances were 68.1±8.0mm (SFB width), 44.3±9.3mm (GFB width), 57.5±15.7mm (STFB width), 52.9±12.1mm (wire to GFB), and 47.9±9.7mm (wire to STFB). Mean coefficients of variation between examiners ranged 9 to 15%. The width and distal most edge of the hamstring fascial band attachments have been quantified. Circumferential release of the fascial connections to the gracilis and semitendinosus is the key to preventing premature amputation. The competency of the fascial attachments to the gracilis and semitendinosus can be visually assessed intraoperatively; when tension is applied to the free ends of these tendons, the skin, which overlies their respective fascial attachments, dimples. The senior author refers to this as the “pucker sign.” Following a complete circumferential release of these fascial attachments this pucker sign is eliminated. Subsequently the tendon stripper may be used without risk of premature amputation.

Complications Related to Hamstring Tendon Harvest

The semitendinosus, gracilis, and patellar tendons are the most commonly harvested grafts for anterior cruciate ligament reconstruction. The use of hamstring autografts offers the advantage of preserved quadriceps function, decreased anterior knee pain, and reduced risk of patellar tendon rupture and patellar fracture when compared with bone–patellar tendon–bone autografts. Harvesting of the semitendinosus and gracilis tendons is, however, not without complications including injuries to branches of the saphenous nerve, donor site pain, medial collateral ligament injury, premature graft amputation, and temporary hamstring weakness. We review the anatomy of the semitendinosus and gracilis tendons, describe potential morbidities of tendon harvesting, and discuss techniques that may minimize these complications.

Localization of the semitendinosus-gracilis tendon bifurcation point relative to the tibial tuberosity: an aid to hamstring tendon harvest

Purpose: Autologous hamstring grafts are commonly used for knee reconstruction. The proximity of the saphenous nerve and its branches, the superficial medial collateral ligament, and the inherent variability of fascial attachments necessitates effective surgical incision placement to minimize tissue morbidity during graft harvest. This study describes a method of locating the semitendinosus and gracilis tendon bifurcation point relative to the tibial tuberosity. It uses a novel diagonal surgical incision placed between a proximal point placed 3 cm medial to the tibial tuberosity and at 3 cm distal and 5 cm medial to the tibial tuberosity. Type of Study: Descriptive. Methods: Thirty-one cadaveric knees (17 right, 14 left) were placed in a jig at 90° flexion. Reference marks were placed over the tibial tuberosity, at 3 cm medial to the tibial tuberosity, and at 3 cm distal and 5 cm medial to the tibial tuberosity. An approximately 3.5-cm-long line (representing the incision) was drawn connecting the 2 points located medial to the tibial tuberosity. After incision, the semitendinosus and gracilis tendon bifurcation point locations were measured with an inflexible metric ruler (± 0.5 cm) and recorded. Results: The mean bifurcation point was located 2.2 ± 0.7 cm distal and 4.5 ± 0.6 cm medial to the tibial tuberosity, directly on the proposed incision line. All bifurcation points were located within ± 2 cm of the proposed incision. Conclusions: The traditionally used incision line is, on average, located 2 cm too lateral to the bifurcation point and in some cases may be located 3 to 4 cm too lateral, making tendon harvest more difficult and more likely to cause harvest-induced injury to adjacent tissues.

Influence of Medial Hamstring Tendon Harvest on Knee Flexor Strength after Anterior Cruciate Ligament Reconstruction

Background The advantages of hamstring tendon autografts for anterior cruciate ligament reconstruction are well known; however, concerns have arisen regarding the influence of hamstring tendon harvest on postoperative weakness in knee flexion. Purpose To evaluate the influence of hamstring tendon harvest on knee flexion strength in patients undergoing anterior cruciate ligament reconstruction. Study Design Prospective randomized study. Methods Ninety patients were randomly assigned at surgery to undergo anterior cruciate ligament reconstruction with either a semitendinosus tendon autograft or a semitendinosus and gracilis tendon autograft. Quadriceps and hamstring muscle strength was tested before surgery and at 6, 12, and 18 months after surgery. Results There was no significant difference in clinical results between the groups and neither group showed a significant decrease in isokinetic hamstring muscle strength. However, when the subjects’ knees were at positions of 70° or more of flexion, both isokinetic and isometric measurements revealed a significant decrease in hamstring muscle strength in both groups. The strength in the group with semitendinosus and gracilis tendons was considerably less than that in the group with semitendinosus tendon alone at 18 months. Conclusions Tendon harvest causes significant weakness of hamstring muscle strength at high knee flexion angles, but such weakness can be minimized if the gracilis tendon is preserved.

Sciatic nerve injury following hamstring harvest

Injury to the sciatic nerve following harvesting of the medial hamstring tendons is a complication that has not been described. I report a unique case of sciatic nerve injury above the level of its bifurcation into its terminal branches following hamstring graft harvest for use in ACL reconstruction. The sciatic nerve anatomy and technique of graft harvest is briefly described.

Magnetic resonance imaging at different time periods following hamstring harvest for anterior cruciate ligament reconstruction

Purpose: The purpose of this study was to evaluate the magnetic resonance imaging (MRI) appearance of the hamstring graft harvest site after harvesting the hamstring tendons to reconstruct a torn anterior cruciate ligament (ACL). Type of Study: Case series. Methods: We performed MRI on 21 patients who had previously undergone hamstring harvest and ACL reconstruction. Twenty of the patients (7 female and 13 male; mean age, 37 years; range, 16 to 84 years), all volunteers, were selected from a series of 45 ACL reconstructions performed by the senior author during a 20-month period. Another patient, a 32-year-old man, underwent ACL reconstruction elsewhere 32 months before. Both the semitendinosus and gracilis tendons were harvested in all cases. All MRIs were obtained on a 1.5-T magnet and were prospectively evaluated by 2 experienced musculoskeletal radiologists who were blinded to the time interval between graft harvest and MRI. Results: Two weeks after graft harvest, MRI showed ill-defined intermediate signal on T1-weighted images and increased signal on T2-weighted images, consistent with fluid in the harvest site, with no discernable tendon. At 6 weeks, structures were seen at the level of the superior pole of the patella that had morphology and signal characteristics similar to native tendon. By 3 months, structures with normal morphology and signal characteristics were seen to the level of the joint line, and by 12 months, to the level of 1 to 3 cm above that of the tibial attachment. At 32 months, the tendons appeared on MRI to normalize to a level of 1 to 2 cm above their tibial attachment. Conclusion: Following hamstring tendon harvest, MRI demonstrates an apparent regeneration of tendons beginning proximally and extending distally over time.Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 17, No 1 (January), 2001: pp 2–8

Ophthalmologic Procedures

Step-by-step instructions for the most common and difficult ophthalmologic procedures that are performed in an emergency department. Foreign body removal, including rust rings, is explained with an emphasis on limiting further injury to the corneal epithelium and stroma. Patching, irrigation, contact lens removal and corneal culture techniques are explained. Three methods of assessing intraocular pressure are described.