Clinical use of fresh, frozen soft tissue allografts

Reconstruction of the Quadriceps Extensor Mechanism with a Calcaneal Tendon-Bone Allograft in a Dog with a Resorbed Tibial Tuberosity Fracture

A non-reducible tibial tuberosity fracture is a rare complication of tibial tuberosity transposition performed during correcting of medial patella luxation (MPL) in dogs. This condition severely disrupts the quadriceps extensor mechanism, leading to significant pelvic limb lameness. An 11-year-old, 1.8 kg spayed female Yorkshire Terrier sustained a comminuted left tibial tuberosity fracture during surgical correction of an MPL. Six months after surgery, the dog was markedly lame and unable to extend the left stifle. Radiographs revealed patella alta and resorption of the fragmented tibial tuberosity. A composite frozen allogeneic calcaneal tendon-bone block was utilized to reconstruct the tibial tuberosity and reattach the patellar ligament. Initial postoperative radiographs confirmed restoration of a normal patellar ligament to patella length ratio (1.42). Both the allogeneic bone used for tibial tuberosity reconstruction and the tendon used to reattach the patellar ligament were successfully integrated. The dog regained satisfactory limb function without recurrence of patella luxation, as reported by the owners 29 months postoperatively. The use of a calcaneal tendon-bone allograft effectively restored the functional integrity of the quadriceps extensor mechanism, providing a viable option for addressing quadriceps insufficiency resulting from the loss of the osseous tibial insertion.

Shape memory histocompatible and biodegradable sponges for subcutaneous defect filling and repair: greatly reducing surgical incision

Reducing surgical incision for large area subcutaneous defect filling and repair is a great challenge in the biomedical field, especially for plastic surgery. In this study, a novel hydroxyethyl cellulose/soy protein isolate (HEC/SPI) composite sponge (EHSS) with a fluid responsive shape memory property was constructed, whose thickness could be controlled by hot-pressing conditions to reduce the required surgical incision greatly. Effects of the main factors such as pressure, temperature and hot-pressing cycles on the recovery degree of EHSS were investigated systematically. The structure and physical properties of the sponges were characterized by FTIR spectroscopy, XRD, SEM etc. The results showed that EHSS could be pressed into thin disks with much smaller thickness, and the thickness retention ratio and recovery ratio were affected by hot-pressing conditions such as pressure and temperature. Especially, EHSS could be hot-pressed into a dense thin disk (EHSS-PT-130) at 130 °C with the pressure of 30 MPa, which could quickly recover its original shape by soaking in hydrophilic fluids. EHSS-PT-130 also exhibited good hydrophilicity, cytocompatibility, histocompatibility and in vivo biodegradability. Compared with the original EHSS, in vivo shape memory EHSS-PT-130 required much smaller surgical incision to reach the same repair effect and no need of extra sterilization, showing potential application for subcutaneous defect filling and repair.

Split Peroneus Longus Free Tendon Autograft Transplantation for the Treatment of Neglected Extensor Hallucis Longus Tendon Laceration: A Case Report

A neglected laceration of the extensor hallucis longus (EHL) tendon is rare. Retraction of the tendon ends often occurs when a laceration is neglected, leading to a substantial tendon deficit. A paucity of case reports is available describing the treatment of EHL laceration with a large area of gap secondary to retraction. Therefore, the treatment recommendations are limited. We present the case of a neglected EHL tendon laceration with a 10.5-cm gap in a healthy 22-year-old female. The EHL tendon laceration was repaired using a split peroneus longus tendon autograft that, to the best of our knowledge, has not been previously reported. At the 3-year follow-up evaluation, the patient retained full function of her hallux and was free of symptoms.

Biologic Scaffolds

Biologic scaffold materials composed of allogeneic or xenogeneic extracellular matrix are commonly used for the repair and functional reconstruction of injured and missing tissues. These naturally occurring bioscaffolds are manufactured by the removal of the cellular content from source tissues while preserving the structural and functional molecular units of the remaining extracellular matrix (ECM). The mechanisms by which these bioscaffolds facilitate constructive remodeling and favorable clinical outcomes include release or creation of effector molecules that recruit endogenous stem/progenitor cells to the site of scaffold placement and modulation of the innate immune response, specifically the activation of an anti-inflammatory macrophage phenotype. The methods by which ECM biologic scaffolds are prepared, the current understanding of in vivo scaffold remodeling, and the associated clinical outcomes are discussed in this article.

Analysis of irradiation on the clinical effectiveness of allogenic tissue when used for primary anterior cruciate ligament reconstruction

BACKGROUND

It is unclear whether the use of low-dose irradiation or other tissue-processing methods, such as preservation by fresh-frozen (FF), freeze-drying (FD), or cryopreservation (CP) methods, affects the clinical outcomes of primary anterior cruciate ligament reconstruction (ACLR) using allograft.

HYPOTHESIS

Low-dose gamma irradiation (<2.5 Mrad) and method of allograft preservation do not affect subjective and objective clinical outcomes after primary ACLR in studies reviewed between November 2010 and September 2012.

STUDY DESIGN

Systematic review; Level of evidence, 3.

METHODS

A computerized search of multiple electronic databases was conducted from November 2010 to September 2012 for prospective and retrospective studies involving primary allograft ACLR. Inclusion criteria were English-language publications with a minimum average of 2 years' follow-up. Studies were excluded if they involved revision surgery, open surgery, multiple ligament procedures, autograft, xenograft, meniscal allograft, skeletally immature patients, or grafts treated with ethylene oxide, Tutoplast, or irradiation>2.5 Mrad or if the tissue-processing methods were not specified. Clinical outcomes were evaluated using the Lysholm score, Tegner score, International Knee Documentation Committee (IKDC) score, KT-1000/2000 arthrometer score, Lachman test, and pivot-shift test, as well as by assessing complications related to graft rupture, revision surgery, and infections.

RESULTS

A total of 21 publications met the criteria, involving a total of 1453 patients, with 415 irradiated and 1038 nonirradiated allografts. Mean follow-up was 49.8 months (range, 12-170 months). Mean age of the patients was 32.2 years. Knees with nonirradiated allografts had higher mean Lysholm scores (89.8 vs 84.4; P<.05), and a higher proportion of <5-mm difference on KT-1000/2000 arthrometer (0.97 vs 0.84; P<.0001), grade 0 and 1 pivot-shift (0.99 vs 0.94; P<.0001), and grade 0 and 1 Lachman (0.94 vs 0.89; P<.01) than those with irradiated grafts. Knees with irradiated allografts had a higher proportion of grade A and B IKDC outcomes (0.91 vs 0.86; P<.05) and revision surgery (0.0250 vs 0.0022; P<.001) compared with those with nonirradiated allografts. The lack of data for FD and CP allografts meant no statistical analysis could be made comparing FF versus FD versus CP allografts. The effect of irradiation was similar within FF allografts. The effect of graft type and surgical technique could not be determined because of insufficient data.

CONCLUSION

These results suggest that primary ACLRs using nonirradiated allografts may provide superior clinical outcomes than those using low-dose (<2.5 Mrad) irradiated grafts.

Autograft versus nonirradiated allograft tissue for anterior cruciate ligament reconstruction: a systematic review

BACKGROUND

An autograft has traditionally been the gold standard for anterior cruciate ligament reconstruction (ACLR), but the use of allograft tissue has increased in recent years. While numerous studies have demonstrated that irradiated allografts are associated with increased failure rates, some report excellent results after ACLR with nonirradiated allografts. The purpose of this systematic review was to determine whether the use of nonirradiated allograft tissue is associated with poorer outcomes when compared with autografts.

HYPOTHESIS

Patients undergoing ACLR with autografts versus nonirradiated allografts will demonstrate no significant differences in graft failure risk, laxity on postoperative physical examination, or differences in patient-oriented outcome scores.

STUDY DESIGN

Systematic review.

METHODS

A systematic review was performed to identify prospective or retrospective comparative studies (evidence level 1, 2, or 3) of autografts versus nonirradiated allografts for ACLR. Outcome data included graft failure based on clinical findings and instrumented laxity, postoperative laxity on physical examination, and patient-reported outcome scores. Studies were excluded if they did not specify whether the allograft had been irradiated. Quality assessment and data extraction were performed by 2 examiners.

RESULTS

Nine studies comparing autografts and nonirradiated allografts were included. Six of the 9 studies compared bone-patellar tendon-bone (BPTB) autografts with BPTB allografts. Two studies compared hamstring tendon autografts to hamstring tendon allografts, and 1 study compared hamstring tendon autografts to tibialis anterior allografts. The mean patient age in 7 of 9 studies ranged from 24.5 to 32 years, with 1 study including only patients older than 40 years and another not reporting patient age. The mean follow-up duration was 24 to 94 months. Six of 9 studies reported clinical graft failure rates, 8 of 9 reported postoperative instrumented laxity measurements, 7 of 9 reported postoperative physical examination findings, and all studies reported patient-reported outcome scores. This review demonstrated no statistically significant difference between autografts and nonirradiated allografts in any outcome measure.

CONCLUSION

No significant differences were found in graft failure rate, postoperative laxity, or patient-reported outcome scores when comparing ACLR with autografts to nonirradiated allografts in this systematic review. These findings apply to patients in their late 20s and early 30s. Caution is advised when considering extrapolation of these findings to younger, more active cohorts.

Cryopreservation with glycerol improves the in vitro biomechanical characteristics of human patellar tendon allografts

PURPOSE

To evaluate the in vitro biomechanical characteristics of patellar tendon ligaments (BTB) when stored as fresh frozen or as glycerol cryopreserved allografts.

METHODS

Seventy patellar tendons were harvested from 35 cadaveric human donors and randomly assigned into seven groups. Grafts in group FRESH were mechanically tested within 2 h of harvesting. FROZ-3, FROZ-6, and FROZ-9 were deep-frozen to -80 °C for 3, 6, and 9 months, respectively. Grafts in groups CRYO-3, CRYO-6, and CRYO-9 were initially incubated with 10% glycerol in a phosphate-buffered saline for 1 h and then stored in glycerol solution (10% glycerol in PBS) at -80 °C for 3, 6, and 9 months, respectively. Grafts were mechanically tested with two cycling modes (50-250 °N and 150-500 °N) and then loaded to failure.

RESULTS

Cryopreserved grafts demonstrated more consistent results and expressed lower elongation rates after both cycling loading protocols compared to their frozen counterparts at all storage times. During load-to-failure analysis, ultimate stiffness levels were predominantly higher (23.9-61.5%) in cryopreserved grafts compared with frozen grafts, and ultimate stress levels were 26% (13.3-47.7%) higher, regardless of the storage time. Moreover, cryopreserved grafts revealed similar ultimate elongation and uniformly higher ultimate stiffness and ultimate stress levels compared to fresh grafts.

CONCLUSION

The results of this in vitro study demonstrated superior mechanical properties of cryopreserved grafts compared to frozen grafts within a preservation period of 9 months. Cryopreservation with glycerol solution might be used to further improve the quality of preserved soft-tissue allografts.

Allograft anterior cruciate ligament reconstruction: indications, techniques, and outcomes

The anterior cruciate ligament (ACL) is an important stabilizer of the knee against translational and rotational forces. The goal of anatomic reconstruction of the ACL-deficient knee is to re-create a stable knee that will allow for return to sport and prevent recurrent injury. Multiple graft options exist for ACL reconstruction, and each option has unique advantages and disadvantages. With appropriate patient selection, each graft can be utilized to optimize patient outcomes. Allograft options limit morbidity following ACL reconstruction, but care must be taken with surgical technique and postoperative rehabilitation to allow for graft incorporation. An understanding of the surgical technique and differences between graft options will allow the patient, surgeon, and physical therapist to maximize outcomes following ACL reconstruction.

Differential cross-linking and radio-protective effects of genipin on mature bovine and human patella tendons

Gamma irradiation is a proven sterilization method, but is not widely used on allografts for anterior cruciate ligament reconstruction (e.g., patella tendon) due to radiation-induced decreases in mechanical strength. Addressing this drawback would improve the safety and supply of allografts to meet current and future demand. It was hypothesized that genipin-induced collagen cross-linking would increase the tensile modulus of patella tendon tissue such that 5 MRad gamma irradiation would not reduce the tissue mechanical strength below the original untreated values. Optimized genipin treatment increased the tensile modulus of bovine tendons by ~2.4-fold. After irradiation, genipin treated tissue did not significantly differ from native tissue, proving the hypothesis. Optimized genipin treatment of human tendons increased the tensile modulus by ~1.3-fold. After irradiation, both control and genipin-treated tissues possessed ~50-60% of their native tendon modulus, disproving the hypothesis. These results highlight possible age- and species- dependent effects of genipin cross-linking on tendon tissue. Cross-linking of human allografts may be beneficial only in younger donor tissues. Future research is warranted to better understand the mechanisms and applications of collagen cross-linking for clinical use.

ACL reconstruction with BPTB autograft and irradiated fresh frozen allograft

OBJECTIVE

To analyze the clinical outcomes of arthroscopic anterior cruciate ligament (ACL) reconstruction with irradiated bone-patellar tendon-bone (BPTB) allograft compared with non-irradiated allograft and autograft.

METHODS

All BPTB allografts were obtained from a single tissue bank and the irradiated allografts were sterilized with 2.5 mrad of irradiation prior to distribution. A total of 68 patients undergoing arthroscopic ACL reconstruction were prospectively randomized consecutively into one of the two groups (autograft and irradiated allograft groups). The same surgical technique was used in all operations done by the same senior surgeon. Before surgery and at the average of 31 months of follow-up (ranging from 24 to 47 months), patients were evaluated by the same observer according to objective and subjective clinical evaluations.

RESULTS

Of these patients, 65 (autograft 33, irradiated allograft 32) were available for full evaluation. When the irradiated allograft group was compared to the autograft group at the 31-month follow-up by the Lachman test, the anterior drawer test (ADT), the pivot shift test, and KT-2000 arthrometer test, statistically significant differences were found. Most importantly, 87.8% of patients in the autograft group and just only 31.3% in the irradiated allograft group had a side-to-side difference of less than 3 mm according to KT-2000. The failure rate of the ACL reconstruction with irradiated allograft (34.4%) was higher than that with autograft (6.1%). The anterior and rotational stabilities decreased significantly in the irradiated allograft group. According to the overall International Knee Documentation Committee (IKDC), functional and subjective evaluations, and activity level testing, no statistically significant differences were found between the two groups. Besides, patients in the irradiated allograft group had a shorter operation time and a longer duration of postoperative fever. When the patients had a fever, the laboratory examinations of all patients were almost normal. Blood routine was normal, the values of erythrocyte sedimentation rate (ESR) were 5~16 mm/h and the contents of C reactive protein (CRP) were 3-10 mg/L.

CONCLUSION

We conclude that the short term clinical outcomes of the ACL reconstruction with irradiated BPTB allograft were adversely affected. The less than satisfactory results led the senior authors to discontinue the use of irradiated BPTB allograft in ACL surgery and not to advocate using the gamma irradiation as a secondary sterilizing method.

Anterior cruciate ligament reconstruction with BPTB autograft, irradiated versus non-irradiated allograft: a prospective randomized clinical study

The effect of using gamma irradiation to sterilize bone-patellar tendon-bone (BPTB) allograft on the clinical outcomes of anterior cruciate ligament (ACL) reconstruction with irradiated allograft remains controversial. Our study was aimed to analyze the clinical outcomes of arthroscopic ACL reconstruction with irradiated BPTB allograft compared with non-irradiated allograft and autograft. All BPTB allografts were obtained from a single tissue bank and the irradiated allografts were sterilized with 2.5 Mrad of irradiation prior to distribution. A total of 102 patients undergoing arthroscopic ACL reconstruction were prospectively randomized consecutively into three groups. The same surgical technique was used in all operations done by the same senior surgeon. Before surgery and at the average of 31 months follow-up (range 24-47 months) patients were evaluated by the same observer according to objective and subjective clinical evaluations. Of these patients, 99 (autograft 33, non-irradiated allograft 34, irradiated allograft 32) were available for full evaluation. When compared the irradiated allograft group to non-irradiated allograft group or autograft group at 31 months follow-up by the Lachman test, ADT, pivot shift test and KT-2000 arthrometer testing, statistically significant differences were found. Most importantly, 87.8% of patients in the Auto group, 85.3% in the Non-Ir-Auto group and just only 31.3% in the Ir-Allo group had a side-to-side difference of less than 3 mm according to KT-2000. The failure rate of the ACL reconstruction with irradiated allograft (34.4%) was higher than that with autograft (6.1%) and non-irradiated allograft (8.8%). The anterior and rotational stability decreased significantly in the irradiated allograft group. According to the overall IKDC, functional, subjective evaluations and activity level testing, no statistically significant differences were found between the three groups. However, there was a trend that the functional and activity level decreased and the patients felt uncomfortable more often in the irradiated allograft group. The statistical analysis showed no significant difference between the non-irradiated allograft group and the autograft group according to the aforementioned evaluations, except that patients in the allograft group had a shorter operation time and a longer duration of postoperative fever. When comparing the postoperative duration of fever of the two allograft groups, there was also a trend that the irradiated allograft group was longer than the non-irradiated allograft group, but no significant difference was found. When the patients had a fever, the laboratory examinations of all patients were almost normal (Blood routine was normal, the values of ESR were 5 - 16 mm/h, CRP were 3 - 10 mg/l). On the basis of our study, we concluded that patients undergoing ACL reconstruction with BPTB non-irradiated allograft or autograft had similar clinical outcomes. Non-irradiated BPTB allograft is a reasonable alternative to autograft for ACL reconstruction. While the short term clinical outcomes of the ACL reconstruction with irradiated BPTB allograft were adversely affected with an increased failure rate. The less than satisfactory results led the senior authors to discontinue the use of irradiated BPTB allograft in ACL surgery and not to advocate that gamma irradiation be used as a secondary sterilizing method. Further research into alternatives to gamma irradiation is needed.

Effects of a novel sterilization process on soft tissue mechanical properties for anterior cruciate ligament allografts

BACKGROUND

Allograft anterior cruciate ligament reconstruction provides benefits such as earlier return to activities and less pain, but concerns remain regarding potential infection and biomechanical stability.

HYPOTHESIS

There is no difference in biomechanical properties of soft tissue allografts treated with the Biocleanse tissue sterilization process compared with irradiated and fresh-frozen allografts.

STUDY DESIGN

Controlled laboratory study.

METHODS

Thirty-six tibialis anterior allografts were equally divided between Biocleanse, irradiated, and fresh-frozen groups. Grafts were measured for cross-sectional area and looped over a smooth rod with the free sutured ends of the graft fixed in custom clamps. Specimens were tensioned to 10 N for 2 minutes and then loaded between 50 and 300 N for 1000 cycles followed by a failure test. Data for creep (mm); stiffness (N/mm) at cycles 1, 10, 100, and 1000; failure load (N); and failure stress (MPa) were compared with a one-way analysis of variance (P < .05).

RESULTS

There were no statistically significant differences in creep between groups. Sterilized groups (irradiated = 144.7 +/- 17.7 N/mm and Biocleanse = 146.5 +/- 28.2N/mm) were significantly stiffer during the first cycle than the fresh-frozen group (117.8 +/- 15.7 N/mm, P < .005) without statistically significant differences for subsequent cycles. There were no differences between groups for either failure load (fresh-frozen = 1665 +/- 291.3 N, irradiated = 1671.9 +/- 290.2 N, Biocleanse = 1651.6 +/- 377.4 N) or failure stress.

CONCLUSION

Data for "time-zero" physiologic stiffness and failure loads indicate that the Biocleanse process does not adversely affect the biomechanical properties of the allograft material.

CLINICAL RELEVANCE

This novel sterilization technique may provide surgeons with potential allograft material with similar biomechanical properties to native tissue.

Reconstruction of the lateral ankle ligaments with allograft in patients with chronic ankle instability

The management of chronic lateral instability of the ankle remains controversial. In general, the anterior talofibular ligament (ATFL) must be reconstructed in all patients. Some will also need reconstruction of the calcaneofibular ligament (CFL) (or its function) to regain stability of both the ankle and the subtalar joints, and to avoid recurrence of instability. After reconstruction, most authors report good to excellent results in 80% to 85% of patients. We describe the augmented reconstruction technique of ATFL and CFL with a semitendinosus tendon allograft through a peroneal bone tunnel fixed with biodegradable anchors, and advocate this procedure as a safe, effective method to manage lateral ankle instability.

The acutely dislocated knee: evaluation and management

Acute knee dislocations are uncommon orthopaedic injuries. Because they often spontaneously reduce before initial evaluation, the true incidence is unknown. Dislocation involves injury to multiple ligaments of the knee, resulting in multidirectional instability. Associated meniscal, osteochondral, and neurovascular injuries are often present and can complicate management. The substantial risk of associated vascular injury mandates that vascular integrity be confirmed by angiography in all suspected knee dislocations. Evaluation and initial management must be performed expeditiously to prevent limb-threatening complications. Definitive management of acute knee dislocation remains a matter of debate; however, surgical reconstruction or repair of all ligamentous injuries likely can help in achieving the return of adequate knee function. Important considerations in surgical management include surgical timing, graft selection, surgical technique, and postoperative rehabilitation.

Surgical reconstruction for chronic lateral instability of the ankle

We have treated 56 patients (56 ankles) for symptomatic chronic lateral ankle instability by the surgical reconstruction procedure. The operation included lateral shift of the entire lateral capsule-ligament complex, suture to anterior border of fibula, and reinforcement by an elevated periosteal flap of distal fibula. These patients were reviewed at a mean period of 3.1 years (range, 9 months to 5 years) after the operation. There were 29 males and 27 females with an average age of 29 years (range, 16-49 years). The clinical results were graded according to the AOFAS Ankle-Hindfoot scales. There were 35 patients who were excellent (above 90 points), 16 who were good (between 76 and 90 points), 4 who were fair (between 60 and 75 points), and 1 who was poor (below 60 points). The excellent and good results amounted to 91.1% (51/56). Therefore, we concluded that symptomatic chronic lateral ankle instability could be successfully managed with this easy and effective surgical reconstruction method.

Endopearl augmentation of bioabsorbable interference screw fixation of a soft tissue tendon graft in a tibial tunnel

In this technical note, we introduce a new technique for tibial side soft tissue graft fixation using a bioabsorbable interference screw augmented with an EndoPearl (Linvatec, Largo, FL) for ACL reconstruction. This technique will enable the knee surgeon to use shorter grafts while minimizing slippage without reducing fixation strength.

The biomechanical effects of low-dose irradiation on bone-patellar tendon-bone allografts

BACKGROUND

Despite evidence that low-dose irradiation of 2 Mrad (20 kGy) is not virucidal for patellar tendon allografts and reduces tissue strength, many tissue bank protocols include low-dose irradiation.

HYPOTHESIS

Maintaining tissue mechanical integrity may be particularly relevant toward accelerated rehabilitation of the injured knee, where the cyclic function of patellar tendon allografts is critical.

STUDY DESIGN

Controlled laboratory study.

METHODS

The cyclic and failure mechanical properties of paired bone-patellar tendon-bone allografts, with and without current low-dose irradiation of 20 kGy, were evaluated. Specimens were loaded from 50 N to 250 N for 1000 cycles at 0.5 Hz and subsequently loaded to failure at a strain rate of 100% per second.

RESULTS

After 1000 cycles, grafts elongated 27% more when irradiated than when not (4.4 +/- 1.5 mm vs 3.4 +/- 1.0 mm; P = .03). Failure load averaged 1965 +/- 512 N for irradiated grafts and 2457 +/- 647 N for nonirradiated grafts (P = .007).

CONCLUSIONS

The diminished strength of irradiated grafts may contribute to overt anterior cruciate ligament graft failure, and the increase in cyclic elongation may also be detrimental to graft function.

CLINICAL RELEVANCE

These results suggest that one should consider the use of nonirradiated allografts as an alternative to irradiated grafts in anterior cruciate ligament reconstruction.

Anterior cruciate ligament reconstruction using cryopreserved allografts

Primary ACL reconstruction historically has been done using autograft tissues whereas allografts have been limited to revision cases and patients who are older or with lower physical demands because some animal studies suggested a slower biologic incorporation rate. The purpose of the current study was to evaluate the effectiveness of the cryopreserved Achilles tendon allograft in primary ACL reconstruction in a consecutive series of athletes. Fifty consecutive patients with a strenuous or moderate preinjury activity level, as defined by the International Knee Documentation Committee (IKDC), had ACL reconstruction using cryopreserved Achilles tendon allografts secured with bioabsorbable interference screws. Five patients were professional athletes. The average age of the patients was 36 years (range, 17-50 years). A 3- to 5-year followup study was done in all of the patients using the IKDC form. Tunnel widening was measured in the lateral radiographs at the widest level. The overall outcome was normal or nearly normal in 94% of the patients. No failures were reported in this series. Forty-six patients (92%) returned to their same preinjury sport activity level. The average KT-1000 side-to-side difference was 2.3 mm. Average tibial tunnel widening was 2.7 mm (range, 0-6 mm); no significant correlation was observed between increased tunnel size and a fair or poor clinical outcome. This experience shows that favorable results can be obtained with cryopreserved Achilles tendon allografts in athletes in whom avoiding donor site morbidity may be an issue in terms of a prompt return to sport.

Surgical treatment of posterior cruciate ligament and posterolateral corner injuries. An anatomical, biomechanical and clinical review

The posterior cruciate ligament has become an increasingly popular subject of orthopaedic research and debate. While biomechanical studies have shown its role as major stabilizer of the knee, clinical studies have shown its increasing incidence. Furthermore, injuries to posterolateral structures are frequently encountered and failure to recognize and treat this associated injury may lead to stretching or failure of the cruciate reconstruction. Surgical reconstruction of isolated/combined injuries is now more effective than before and different technical options are now available for the surgeon, even if much work remains ahead of us as we try to understand how to successfully treat these complex knee injuries.

Soft tissue allografts for knee reconstruction in sports medicine

Soft tissue allografts are an important substitute tissue for the reconstruction of deficient ligaments, torn menisci, and osteochondral defects during knee surgery. Interest in allografts for soft tissue reconstruction has arisen from the demand to obtain a stable knee with restoration of function and protection against additional injury. Use of allografts for soft tissue reconstruction is associated with less donor tissue site morbidity and reduced surgical time. Nevertheless, use of allografts has a potential for disease transmission, delayed graft incorporation, and host versus donor immunologic response to the graft. Experimental studies and animal models have provided information about the biologic aspects of graft incorporation and remodeling and have contributed to the development of methods of graft preparation and transplantation. Clinical studies of allograft transplantation in humans have helped to define surgical indications and techniques and have allowed for the assessment of clinical outcome. The current authors review the current literature concerning the basic and clinical principles of soft tissue allografts for knee reconstruction, and underscore the scientific basis for the clinical application of allograft tissue during knee surgery.

Extensor hallucis longus tendon rupture repair using a fascia lata allograft

The authors present a case of a traumatic extensor hallucis longus tendon rupture sustained 2 days after hallux valgus and hammer toe correction. The ruptured tendon, separated by a 6-cm defect, was repaired using a fascia lata allograft. This case demonstrates a serious complication of a commonly performed procedure and a salvage technique useful for dealing with large tendon defects.

Evaluation of frozen subepithelial connective tissue grafts to increase the zone of attached gingiva. Report of 5 cases

BACKGROUND

In the past decade, gingival tissue has been regenerated using subepithelial connective tissue grafts (SECT). This report presents the use of frozen subepithelial connective tissue (FSECT) for increasing the zone of attached keratinized gingiva (KG).

METHODS

Five cases, 4 females and 1 male, aged 55 to 73 years, presented with inadequate attached KG. The SECT grafts were harvested from the palatal flap during conventional flap surgery. All grafts were frozen immediately. Five weeks to 10 months later, the grafts were placed in areas in which patients had inadequate KG.

RESULTS

In all cases, healing was uneventful. All cases were followed up 3 months to 1.5 years. An increase of 1 to 3 mm of KG was achieved.

CONCLUSIONS

These cases show that the FSECT graft is useful in treating mucogingival problems. Further randomized controlled trials over long periods of time are necessary to establish whether this procedure offers long-term benefits to patients.

Outcome measurement in the ACL deficient knee--what's the score?

There is increasing pressure within the United Kingdom for transparent assessment of the performance of every doctor along with the procedures they perform. Unfortunately, the validation of the outcome measures used to assess such procedures has been questioned. This has been well illustrated in the anterior cruciate ligament (ACL) deficient knee. Over 54 different outcome measures used to assess the ACL deficient knee have been identified, few of which were formally assessed at their initial publication. For those most frequently used the Lysholm (I and II) knee scoring scale and Tegner activity score are the only ones to have been adequately validated prior to use. The Cincinnati rating system and International Knee Documentation Committee (IKDC) form were not assessed and the reliability of both measures has since been questioned. Appropriately tested newer measures include the IKDC subjective knee evaluation form, Mohtadi's ACL quality of life outcome measure and the Knee injury and osteoarthritis outcome score (KOOS). We recommend use of the Lysholm II knee scoring scale and Tegner activity score for clinical follow-up of patients and for use as a gold standard to which future measures can be compared. These have their deficiencies and will ultimately require replacement. In view of the international standing of its authors, the IKDC subjective knee evaluation form is likely to be used in preference to the KOOS despite its attractions. For long-term clinical trials the SF-36 should also be used. Further research is required to produce suitable measures for assessing the ACL deficient knee and this work should be appropriately funded.

Arthroscopic anterior cruciate ligament reconstruction with quadriceps tendon-patellar bone autograft

BACKGROUND

Surgical reconstruction of the anterior cruciate ligament (ACL) is indicated in the ACL-deficient knee with symptomatic instability and multiple ligaments injuries. Bone patellar tendon-bone and the hamstring tendon generally have been used. In the present study, we describe an alternative graft, the quadriceps tendon-patellar bone autograft, by using arthroscopic ACL reconstruction.

METHODS

From March of 1996 through March of 1997, a quadriceps tendon-patellar bone autograft was used in 12 patients with ACL injuries.

RESULTS

After 15 to 24 months of follow-up, the clinical outcome for those patients with this graft have been encouraging. Ten patients could return to the same or a higher level of preinjury sports activity. According to the International Knee Documentation Committee rating system, 10 of the 12 patients had normal or nearly normal ratings. Recovery of quadriceps muscle strength to 80% of the normal knee was achieved in 11 patients in 1 year.

CONCLUSION

The advantages of the quadriceps tendon graft include the following: the graft is larger and stronger than the patellar tendon; morbidity of harvest technique and donor site is less than that of patellar tendon graft; there is little quadriceps inhibition after quadriceps harvest; there is quicker return to sports activities with aggressive rehabilitation. A quadriceps tendon-patellar autograft is a reasonable alternative to ACL reconstruction in patients who are not suitable for either a bone-patellar tendon-bone autograft or a hamstring tendon autograft.

Revision anterior cruciate ligament surgery: experience from Pittsburgh

Twenty-five patients who underwent revision anterior cruciate ligament reconstruction after failure of a previous intraarticular reconstruction were retrospectively reviewed. Before revision, all patients reported functional instability with sports or activities of daily living and exhibited increased anterior patholaxity on physical examination. Fresh frozen irradiated allograft tissue was used for all revisions. A comprehensive knee analysis using a subjective and objective system was done for all patients preoperatively and at the time of final followup. The mean age at revision surgery was 25 years and average time from primary to revision surgery was 30 months. Average length of followup was 28 months. The anteroposterior displacement was improved in all patients. Sixty-four percent of patients had less than 5 mm side to side difference on arthrometric testing. Eighty percent had either a Grade 0 or Grade 1 pivot shift. The average modified Cincinnati Knee Score was 68 with the results of 88% of patients rated abnormal by International Knee Documentation Committee guidelines. Seventy-six percent of patients were satisfied with their results and would elect to have revision surgery again. These results show that patients having revision anterior cruciate ligament reconstruction for a failed intraarticular reconstruction had improvement in their functional status compared with prerevision; however, they did not achieve the same level of satisfactory results as primary anterior cruciate ligament reconstruction.

Anterior cruciate ligament surgery 1996. State of the art?

During the past 20 years, numerous basic science and clinical studies have improved the treatment of the anterior cruciate ligament deficient knee. As our understanding of the short term and long term morbidity caused by the torn anterior cruciate ligament has improved, and the morbidity of surgical reconstruction has decreased, the indications for anterior cruciate ligament reconstruction have widened. Anatomic placement of the anterior cruciate ligament graft has improved the outcome of surgery, although various techniques are used to achieve that goal. The patellar tendon autograft has been established as the gold standard graft choice, but several graft choices are available, and have given similar results in early followup. One of the major advances in anterior cruciate ligament reconstruction has been the acceptance of early range of motion and controlled endurance and strength training during the postoperative period.

Allograft versus autograft anterior cruciate ligament reconstruction: 3- to 5-year outcome

Sixty-four patients whose knees underwent anterior cruciate ligament reconstruction with nonirradiated allograft tissue were compared with 26 patients whose anterior cruciate ligaments were reconstructed using autograft tissue 3 to 5 years after their operation. Detailed symptoms, activity-level, and functional outcomes, physical examination, and instrumented knee testing were recorded. No statistically significant differences were found except a higher incidence of loss of terminal extension in the autograft group. These differences were small and not considered clinically significant. Laxity and knee scores were similar in both groups. According to International Knee Documentation Committee ratings, overall outcome was normal or nearly normal in 48% of the allograft patients and in 38% of the autograft patients. Overall subjective rating with the Cincinnati Knee Score was 85.8 for the allograft patients and 84.5 for the autograft patients. Allograft tissue provides an acceptable alternative to autograft tissue for reconstruction of the anterior cruciate ligament.

Graft failure in intra-articular anterior cruciate ligament reconstructions: a review of the literature

There exists a substantial group of patients with unsatisfactory results following anterior cruciate ligament (ACL) reconstructions. This may be attributable to graft failure. Revision surgery, for the correction of abnormal anterior translation of laxity, requires a careful analysis of the causes of failure to ensure the success of the salvage procedure. This review attempts to present an overview of some of the important studies in the literature pertaining to the intraoperative and postoperative factors that probably cause graft failure. It was done by initial identification of the articles from a Medline database followed by the use of cross references. It shows that failures can be minimised by adhering to the correct operative and post-operative techniques wherein proper attention to the factors, such as: adequate notchplasty, proper tunnel placements, proper tensioning, adequate fixation, optimal selection and harvest of the graft, and rehabilitation, are ensured.

Anterior cruciate ligament reconstruction: endoscopic versus two-incision technique

The purpose of this study was to compare the single-incision, "endoscopic" (ENDO) anterior cruciate ligament (ACL) reconstruction technique with the two-incision, "rear-entry" technique (RE). Sixty patients were entered into a prospective study. Thirty patients underwent ACL reconstruction by the RE technique, followed by 30 consecutive patients using the ENDO procedure. Postoperatively all patients followed a standardized rehabilitation protocol. Follow-up evaluation consisted of a detailed physical examination, range of motion, thigh girth, vertical leap, hop test, KT-1000 testing, and patient interview. They were scored according to the International Knee Documentation Committee (IKDC) protocol, which takes objective and subjective data into account. Patients were also assessed for level of sports activity including frequency and type. Finally, anteroposterior and lateral x-ray films were evaluated with a scoring system for tunnel location. Of the initial 60 patients entered into the study, 50 were available for a detailed clinical and functional review (83%). Demographic comparisons revealed 24 RE patients and 26 ENDO patients. There were 16 men and 8 women in the RE group. The ENDO group comprised 16 men and 10 women. There were 14 right knees and 10 left knees in the RE group. In the ENDO group there were 13 right knees and 13 left knees. The average age in the RE group was 24 years and 25 years in the ENDO group. The average follow-up was 35 months (range 31-40 months) in the RE group and 29 months (range 24-35 months) in the ENDO group. Complications included two patients with loss of motion in the RE group and three in the ENDO group. There were no significant differences between the two groups tested with respect to the overall IKDC rating scale. Anteroposterior and lateral x-ray films revealed no significant differences in femoral and tibial tunnel placement. In conclusion, no significant functional or radiographic differences at a minimum 2-year follow-up could be identified when comparing the two ACL reconstructive techniques.

Osgood-Schlatter's disease complicating anterior cruciate ligament reconstruction

Osgood-Schlatter's disease (OSD) is generally felt to be a benign self-limited disorder. In a small number of patients a symptomatic free bone ossicle persists at the tibial insertion of the patellar tendon. We report the case of a collegiate soccer player with a history of OSD who sustained an acute rupture of his anterior cruciate ligament (ACL). The presence of a free bone ossicle in his patellar tendon necessitated modification of our routine approach to ACL reconstruction. Awareness of the potential for patellar tendon graft problems in patients with previous OSD will allow surgeons to plan alternative reconstructive techniques based on the specific needs of the patient.