Injury of the infrapatellar branch of the saphenous nerve due to hamstring graft harvest

The prognosis of iatrogenic saphenous nerve injuries during hamstring tendon harvesting in anterior cruciate ligament reconstruction

PURPOSE

This study aims to evaluate the long-term outcomes of saphenous nerve (SN) injuries from hamstring tendon harvesting during ACL reconstruction, focusing on clinical results and patient satisfaction after at least two years. Additionally, it investigates the incidence, recovery patterns, and impact of these injuries on functional outcomes, daily activities, and ACL re-rupture rates immediately post-surgery and at final follow-up.

MATERIALS AND METHODS

A retrospective review was conducted on patients who had undergone ACL reconstruction with hamstring tendon grafts at a single institution between January 2015 and January 2020. The incidence of SN injuries was assessed immediately after surgery and at final follow-up. Additionally, the recovery rate and time were evaluated, and the impact of these injuries on functional outcomes was measured using the Lysholm Knee Score (LKS) and patient-reported effects on daily activities.

RESULTS

Of the 159 patients analyzed, iatrogenic SN injuries were initially observed in 87 (54.7%) patients post-ACLR. By the final follow-up, paresthesia had resolved in 36 (22.6%) patients within an average of 11.1 months. Persistent SN injuries were recorded in 51 (32.1%) patients, affecting various extents of the infrapatellar branch (IPBSN) and the sartorial branch (SBSN) of the saphenous nerve. Patients with persistent SN injuries experienced a significant impact on daily activities and had lower LKS scores compared to those without injuries or with recovered injuries. Furthermore, a higher re-rupture rate was associated with persistent SN injuries.

CONCLUSIONS

The study finds that SN injuries during hamstring graft harvesting for ACL reconstruction are common, with a significant portion of patients experiencing persistent sensory deficits for at least two years postoperatively. These injuries are observed to adversely affect patient satisfaction and functional outcomes and to increase the re-rupture rate.

A comparative study of Infra patellar branch of saphenous nerve injury between vertical and horizontal portal incisions in knee arthroscopy

Background

An Infrapatellar Branch of Saphenous Nerve (IPBSN) injury is one of the complications leading to sensory loss in the operated knee. A high incidence of IPBSN injury was reported during hamstring harvest, but there are only a few studies analyzing IPBSN injury during arthroscopy portals. However, there was a lack of randomized comparative studies comparing the incidence of IPBSN injury in horizontal and vertical portals. This study aimed to identify the overall incidence of IPBSN injury and compare the difference between vertical and horizontal portal incisions. We also aimed to observe the recovery pattern of IPBSN injuries in both groups. We hypothesize that since the portal incisions are very small, the incidence of IPBSN injury will be very low, and it will occur more in the vertical incision.

Methods

After obtaining IRC approval from B&B Hospital IRC, this prospective comparative study was conducted at the AKB center for arthroscopy, sports injury, and regenerative medicine, B&B Hospital. The calculated sample size of 128 consecutive patients was included and divided into groups by the block randomization method. A total of 64 patients were allocated to both groups. Demographic data was recorded. The sensory loss along the IPBSN was examined and documented on the first postoperative day. Their recovery was documented during two weeks and three months of follow-up visits. Parametric and non-parametric tests were applied to analyze the variables.

Results

IPBSN injury was seen in 12 patients (9.37 %) among 128 study participants. Five patients (7.81 %) had IPBSN injuries in the vertical group compared to seven (10.93 %) in the horizontal group. Recovery was earlier in the horizontal incision group.

Conclusion

The overall incidence of IPBSN injury during the arthroscopy portal is low. They occur equally in vertical and horizontal portal incisions. The recovery of the IPBSN injury was better and earlier in the horizontal incision group.

Surgical Treatment of Saphenous Nerve Injury Assisted by Plasma Rich in Growth Factors (PRGF): Lessons from a Case Report

The infrapatellar branch of the saphenous nerve (SN) is a widely described anatomic and functional structure; however, its relevance in daily clinical practice is underestimated. All surgical procedures performed on the anteromedial aspect of the knee are associated with a risk of iatrogenic injury to this nerve, including knee arthroscopy, knee arthroplasty, tibial nailing, etc. We present the case of a saphenous nerve neuroma after treatment with radiofrequency thermal ablation due to a knee pain problem. After conducting an anaesthetic suppression test, we decided to perform a denervation of the medial saphenous nerve in Hunter's canal. We performed surgery on the anteromedial aspect of the knee. The distal end of the medial SN was coagulated with a bipolar scalpel. The proximal end of the nerve was released proximally, and a termino-lateral suture was made at the free end of the nerve after creating an epineural window to inhibit its growth. A double crush was produced proximally to the suture site to create a grade II-III axonal injury. Autologous plasma rich in growth factors (PRGF) was used to reduce potential post-surgical adhesions and to stimulate regeneration of the surgical lesions. One year after surgery, the patient was living a completely normal life.

Outside-in technique versus inside-out semitendinosus graft harvest technique in ACLR: a randomised control trial

Background

Paraesthesia after hamstring graft harvest is a ubiquitous complication in the early post-operative period, and its correlation with vertical versus horizontal skin incision are well documented. The purpose of the study is to evaluate the incidence and extent/area of sensory loss of saphenous nerve branches occurring with the outside-in (OI) versus inside-out technique (IO) of semitendinosus graft harvest from the sartorius fascia and to determine a better method of graft harvest.

Methods

Sixty patients who underwent isolated semitendinosus graft harvest during anterior cruciate ligament reconstruction (ACLR) between 2016 and 2017. Patients were randomised into two groups depending on the graft harvest technique: 30 in the OI group and 30 in the IO group. The area of sensory loss was mapped on the patients’ skin using tactile feedback from the patients at each follow-up (10 days, 1 month, 3 months, 6 months and 1 year). Then, the area of sensory changes for the infrapatellar branch (IPBSN) and sartorial branch (SBSN) of the saphenous nerve, incision length, graft harvest duration, and graft length were analysed statistically between the groups.

Results

In groups 1 and 2, 18/30 (60%) and 19/30 (63%) of patients, respectively, developed sensory changes, with no significant difference between the groups (p = 0.79). Isolated SBSN and IPBSN paraesthesia occurred in 2/60 (3%) and 19/60 (32%), respectively. Combined SBSN and IPBSN paraesthesia was present in 16/60 (27%) of patients. There was no significant difference in the area of the sensory deficit between OI and IO groups on the 10th post-operative day or at 1-month, 3-month or 1-year follow-up (p = 0.723, p = 0.308, p = 0.478, p = 0.128, respectively). However, at 6-month follow-up, the area of paraesthesia was significantly higher in the IO group (p = 0.009). The length of incision and duration of graft harvest was higher in the OI group than in the IO group (p = 0.002 and p = 0.007, respectively), and the total length of the graft was greater in the IO group (p = 0.04).

Conclusion

Incidence is equally distributed, area of iatrogenic saphenous nerve injury gradually decreases, and recovery is seen in the majority of the patients in both graft harvest techniques. IO graft harvesting technique is better in terms of graft harvest time and cosmetics and yields longer graft; however, area of paraesthesia, though not significant, was two-fold higher than the OI technique at 1-year follow-up.

Clinical relevance

IO graft harvest technique would enable the surgeon to adopt quicker graft harvest, smaller surgical scar and lengthier graft than the OI technique.

Level of evidence

Therapeutic randomised controlled prospective study, Level II.

A modified oblique incision in hamstring tendon graft harvesting during ACL reconstruction

BACKGROUND

During anterior cruciate ligament (ACL) reconstruction, different methods of harvesting hamstring tendon may lead to different degrees of injury to the inferior patellar branch of the saphenous nerve (IPBSN). Most of recent studies in the literature suggest that the classic oblique incision (COI) can reduce the incidence of IPBSN injury. We proposed a modified oblique incision (MOI) and compared it with the COI in terms of the resulting levels of injury and sensory loss and the clinical outcome.

METHODS

Patients with ACL injury admitted to our hospital from April 2015 to July 2019 were randomly selected and included in our study. Thirty patients underwent the COI to harvest hamstring tendons, and the other 32 patients underwent the MOI. The pin prick test was performed to detect the sensation loss at 2 weeks, 6 months, and 1 year after the operation. Digital photos of the region of hypoesthesia area were taken, and then, a computer software (Adobe Photoshop CS6, 13.0.1) was used to calculate the area of the hypoesthesia. The length of the incision and knee joint functional score were also recorded.

RESULTS

At the final follow-up, the incidence of IPBSN injury in COI and MOI were 33.3% and 9.4%, and the areas of paresthesia were 26.4±2.4 cm² and 9.8±3.4 cm² respectively. There was no significant difference in the incision length or knee functional score between the two groups.

CONCLUSION

The MOI can significantly reduce the risk of injury to the IPBSN, reduce the area of hypoesthesia, and lead to high subjective satisfaction. Therefore, compared with the COI, the MOI is a better method of harvesting hamstring tendons in ACL reconstruction.

Lower donor-site morbidity using QT autografts for ACL reconstruction

PURPOSE

Comparing scar cosmesis and regional hypoesthesia at the incision site between quadriceps tendon (QT), bone-patellar tendon-bone (BPTB), and hamstring tendon (HT) for anterior cruciate ligament (ACL) reconstruction.

METHODS

Ninety patients undergoing ACL reconstruction with QT, HT or BPTB were evaluated at 1-year post-op. Scar cosmesis was assessed using the patient and observer scar assessment scale (POSAS) and length of the incision. Sensory outcome was analyzed by calculating the area of hypoesthesia around the scar. The classical ACL reconstruction functional follow-up was measured using the Lysholm score and KOOS.

RESULTS

Concerning QT versus BPTB group, QT patients have a significantly lower mean POSAS (24.8 ± 6.3 vs. 39.6 ± 5.8; p < 0.0001), shorter mean incision (2.8 ± 0.4 cm vs. 6.4 ± 1.3 cm; p < 0.0001), lower extent of hypoesthesia (8.7 ± 5.1 cm² vs. 88.2 ± 57 cm²; p < 0.0001), and better Lysholm score (90.1 ± 10.1 vs. 82.6 ± 13.5; n.s.). No significant difference was seen in KOOS (90.7 ± 7.2 vs. 88.4 ± 7.0; n.s.). Concerning QT versus HT group, no significant difference was found regarding mean POSAS score (24.8 ± 6.3 vs. 31.8 ± 6.2; n.s.), mean length of the incision (2.8 ± 0.4 cm vs. 2.5 ± 0.6 cm; n.s.), KOOS (90.7 ± 7.2 vs. 89.8 ± 8.2; n.s.) and mean Lysholm score (90.1 ± 10.1 vs. 87.8 ± 0.6; n.s.). The mean measured area of hypoesthesia was significantly higher in the HT group (70.3 ± 77.1 cm² vs. 8.7 ± 5.1 cm²; p < 0.0001).

CONCLUSION

Quadriceps tendon harvesting technique has the safest incision by causing less sensory loss compared to BPTB and HT. It also has the advantage of a short incision with more cosmetic scar compared to BPTB, with no difference compared to HT. However, no significant difference in terms of functional outcome was shown between the three autografts. These findings provide surgeons evidence about their clinical practice and help with graft choice decisions.

LEVEL OF EVIDENCE

III.

No difference in sensory outcome between vertical and oblique incisions for hamstring graft harvest during ACL reconstruction

PURPOSE

To compare the incidence, extent of sensory loss, its clinical effect and natural course caused by sensory nerve injury, during two different skin incisions used for autogenous hamstring graft harvest during ACL reconstruction.

METHODS

This randomized prospective study was carried out on 84 patients, divided into two groups, all of them underwent arthroscopic ACL reconstruction using hamstring tendon graft with two incisions; a vertical incision used in 43 patients, and an oblique incision in 41 patients. The location and area of sensory loss were evaluated during follow-up as well as the degree of improvement and patient satisfaction.

RESULTS

The average age in this study was 29.8 ± 7.2 in the vertical group and 29.9 ± 6.3 in the oblique group. Both semitendinosus and gracilles were harvested in 34 patients, semitendinosus in 49 patients and gracilles in one patient. In the vertical group, a higher incidence of sensory loss was recorded with 21 patients (51.2%), relative to the oblique group with 18 patients (41.9%). However, there was no statistically significant difference (p = n.s). Most of the sensory loss affected the distribution of the IPBSN (infrapatellar branch of saphenous nerve) in 27 patients (69.2%) in both groups, and to a lesser extent in the lower medial area [distribution of SBSN (sartorial branch of saphenous nerve)] in 12 patients (30.8%).

CONCLUSION

This study clearly revealed the high incidence of nerve injury particularly the IPBSN during hamstring graft harvest, but did not prove a difference between oblique and vertical incisions, with regard to postoperative sensory loss. It was clear that harvesting the semitendinosus alone is not a factor that can diminish nerve injury.

LEVEL OF EVIDENCE

II.

Association between incision technique for hamstring tendon harvest in anterior cruciate ligament reconstruction and the risk of injury to the infra-patellar branch of the saphenous nerve: a meta-analysis

PURPOSE

To determine how the incision technique for hamstring tendon (HT) harvest in anterior cruciate ligament (ACL) reconstruction affects the risk of injury to the IPBSN and clinical outcome.

METHODS

A systematic literature search of the MEDLINE/Pubmed, Cochrane Central Register of Controlled Trials (CENTRAL) and EBSCOhost electronic databases and clinicaltrials.gov for unpublished studies was performed to identify comparative studies investigating injury to the IPBSN after HT ACL reconstruction by comparing at least two different incision techniques. Data were extracted for the number of patients with evidence of any neurologic deficit corresponding to injury to the IPBSN, area of sensory deficit, the Lysholm score and patient satisfaction. The mean difference (MD) in study outcome between incision groups was assessed. The relative risk (RR) and the number needed to treat (NNT) were calculated. The Chi-square and Higgins' I² tests were applied to test heterogeneity. Data were pooled using a Mantel-Haenszel random-effects model if the statistical heterogeneity was > 50% and a fixed-effects model if the statistical heterogeneity was < 50%. The risk of bias was evaluated according to the Cochrane Database questionnaire and the quality of evidence was graded according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) guidelines.

RESULTS

A total of eight studies (three randomized controlled trials (RCTs) and five comparative studies) were included, of which six compared vertical and oblique incisions, one horizontal and vertical incisions, and one compared all three techniques. HT harvest was performed through a vertical incision in 329 patients, through an oblique incision in 195 patients and through a horizontal incision in 151 patients. Considering the meta-analysis of the RCTs, the performance of a vertical incision significantly increased the risk of causing IPBSN deficiency compared with both oblique and horizontal incision [RR 1.65 (CI 1.10-2.49, p = 0.02) and RR 2.45 (CI 1.73-3.47, p < 0.0001), respectively]. A significantly larger area of sensory deficit was found with vertical incisions compared with oblique ones, with an MD of 22.91 cm² (95% CI 7.73-38.08; p = 0.04). No significant differences were found between the incision techniques in relation to patient-reported outcomes. The same trend was obtained after the performing a meta-analysis of all eight included studies. The quality of evidence in this meta-analysis was determined as "low" to "moderate", mostly due to inadequate methods of randomization and high heterogeneity among the included studies.

CONCLUSION

The performance of a vertical incision to harvest HTs for ACL reconstruction significantly increased the risk of iatrogenic injury to the IPBSN compared with both oblique and horizontal incisions.

LEVEL OF EVIDENCE

Level I-III, meta-analysis of comparative studies.