Table 3.

GRADE Evidence Profile: Efficacy and Safety of Allografts in PCL Reconstruction

Certainty Assessment							Number of Analyzed Patients∗		Effect	Certainty	Importance
Number of Studies	Study Design	Risk of Bias	Inconsistency	Indirectness	Imprecision	Other Considerations	Allograft	Autoraft
Effectiveness
Patient-reported function, activity level and symptoms (follow-up: mean >2 years; assessed with: Lysholm score)
21,2,25,26	Randomized trials	Very serious∗,†	Serious‡	Not serious	Not serious	None	50	58	None of the studies found a statistically significant difference in the Lysholm score between treatment groups postoperatively. Li et al.25: 85.2 ± 3.9 vs 87.8 ± 3.6, diff. n. s. with P > 0.05 Wang et al.26: 92.3 ± 6.8 vs 87.8 ± 9.6, diff. n. s. with P > 0.05	⊕◯◯◯ Very low	Critical
Patient-reported function, activity level and symptoms (follow-up: mean > 2 years; assessed by Tegner score)
21,2,25,26	Randomized trials	Very serious∗,†	Not serious	Not serious	Not serious	None	50	58	None of the studies found a statistically significant difference in the Tegner score between treatment groups postoperatively. Li et al.25: 6.2 ± 1.7 vs 6.8 ± 1.1, diff. n. s. with P > 0.05 Wang et al.26: 4.7 ±1.66 vs. 4.73 ±1.66, diff. n. s. with P > 0.05	⊕⊕◯◯ Low	Critical
Patient-reported function, activity level and symptoms (follow-up: mean 5.6 years; assessed with: subjective IKDC score)
12,25	Randomized trials	Serious†	Not serious	Not serious	Serios§	None	27	26	Mean postoperative subjective IKDC score: 80.2 ± 6.8 vs 83.5 ± 6.3, diff. n. s. with P > 0.05	⊕⊕◯◯ Low	Critical
Clinical knee stability (follow-up: mean 2.8 years assessed by the Reverse Lachman test)
126	Randomized trials	Very serious∗	Not serious	Not serious	Not serious	None	23	32	The study did not find a statistically significant difference in the reverse Lachman test postoperatively. Mean postoperative reverse Lachman test score: 0.7 ± 0.56 vs 0.75 ± 0.67, diff. n. s. with P > 0.05	⊕⊕◯◯ Low	Important
Clinical knee stability (assessed with: Reverse Pivot shift test)
125	Randomized trials	Serious†	Not serious	Not serious	Not serious	None	27	26	Postoperative reverse Pivot shift (Grade 0-1): 26/27 (96.3%) vs 26/26 (100%), diff. n. s. with P > 0.05	⊕⊕⊕◯ Moderate	Important
Clinical knee stability (follow-up: mean >2 years; assessed with: KT arthrometer; better indicated by lower values)
225,26	Randomized trials	Very serious∗,†	Serious‖	Not serious	Not serious	None	50	58	1 study found a statistically significant difference favoring autografts, while another study did not find any statistically significant difference based on the side-to-side difference measured by an instrumented knee laxity test. Side-to-side difference in mm: Li et al.25: 3.5 ± 1.1 vs 2.1 ± 1, diff. s. s. with P < 0.001 Wang et al.26: 2.83 ± 1.7 vs 3.16 ± 2.6, diff. n. s. with P > 0.05	⊕◯◯◯ Very low	Important
Clinical knee stability (follow-up: mean >2 years; assessed by objective IKDC)
225,26	Randomized trials	Very serious∗,†	Not serious	Not serious	Not serious	None	50	58	None of the studies found a statistically significant difference in the objective IKDC score between treatment groups postoperatively. Objective IKDC (normal and nearly normal): Li et al.25: 24/27 (88.9%) vs 25/26 (96.2%) Wang et al.26: 14/23 (60.9%) vs 23/32 (71.9%)	⊕⊕◯◯ Low	Important
Safety
Reoperations (follow-up: mean 5.6 years)
125	Randomized trials	Not serious	Not serious	Serious2,¶	Serious#	None	27	26	The study stated that no patient needed additional surgery because of recurrent or residual posterior laxity: 0% vs 0% (further information: NR).	⊕⊕◯◯ Low	Critical
225,26	Randomized trials	Serious	Not serious	Not serious	Serious§	None	50	58	Overall complication rate (reported in 1 study26): 0/23 (0) vs 7/32 (21.9%). Infections: Li et al25: no postoperative infection; Wang et al.26: 0/23 (0) vs 2/32 (6.3%; 1 acute and 1 late infection) Deep venous thrombosis (reported in 1 study25): 0/27 (0) vs 0/26 (0) Further reported complications: Donor site symptoms in 1 study 26: 0/23 (0) vs 4/32 (12.5%); Reflex sympathetic dystrophy in 1 study 26: 0/23 (0) vs 1/32 (3.1%) Li et al.25 further stated narratively that no postoperative infection, no deep venous thrombosis, no cases of major neurovascular, infectious, vascular, deep venous thrombosis or wound complications in any of the 80 analyzed patients (of whom 27, 26 and 27 received allografts, autografts and hybrid grafts, respectively) occurred. Tibial and femoral tunnel enlargement in 1 study26: Tibial: 12 ± 20 (range: 0-90) vs 12 ± 14 (range: 0-43), n. s. with P = 0.64 Femoral: 5.3 ± 22 (range: 0-50) vs 13 ± 19 (range: 0-55), n. s. with P = 0.771	⊕⊕◯◯ Low	Critical

CI, confidence interval; IKDC, International Knee Documentation Committee; MD, mean difference.

^∗In Wang et al., there was high risk of bias for selection bias and unclear risk of bias as to whether patients were blinded.

^†In Li et al., it was unclear whether the random sequence generation was adequate (selection bias), and whether patients were blinded.

^‡None of the studies showed any statistically significant differences postoperatively in the Lysholm score between the allograft and the autograft groups. The non-statistically significant differences were not unanimously higher in one treatment group. This may be an indicator for heterogeneity. A calculation of the i-square is further needed to adequately assess how heterogeneous the results for this outcome may be.

^§The optimal information size may have not been reached.

^‖Heterogeneity may have been present because study results were not unanimous. Further calculation of the i-square is needed to elaborate on the extent of the heterogeneity.

^¶The study referred to the patients who did not need additional surgery because of recurrent or residual posterior laxity. It was unclear to the review authors whether this refers to the overall reoperations rate or only the patients with recurrent or residual posterior laxity.

^#The optimal information size may have not been reached.