Keywords
arthroplasty, replacement, hip - injections, intra-articular - analgesia - rehabilitation
Introduction
Total hip arthroplasty (THA) consists of the surgical treatment of patients with advanced coxarthrosis, chronic pain, significant functional limitation, and no improvement under conservative treatment.[1] Total hip arthroplasty improves pain, quality of life, and psychosocial features of these subjects.[2]
In addition, THA is the treatment of choice for displaced femoral neck fractures in patients over 60 years old who are active, healthy, and have a good life expectancy.[3]
Nevertheless, many patients present moderate-to-severe pain after the procedure, resulting in prolonged hospitalization and increased postoperative complications.[4] An ideal postoperative THA analgesia regimen should preserve early knee and hip mobility, allow early physical therapy, accelerate recovery, shorten hospital stay, reduce the risk of postoperative complications, and increase patient satisfaction.[5]
Kerr and Kohan[6] developed the local infiltration analgesia (LIA) technique in 2008. Local infiltration analgesia consists of the intraoperative intra-articular injection of a mixture of ropivacaine, ketorolac, and epinephrine for postoperative analgesia with lower rates of side effects or complications compared with other analgesic techniques.[7]
[8]
[9]
[10]
[11]
[12]
However, many studies observed no significant difference between groups, and there is still controversy whether periarticular infiltration provides greater analgesia and early recovery after THA.[13]
[14]
[15]
The technical details of periarticular infiltration vary significantly among surgeons, with little standardization. Nociceptor location in the hip determines the preferred infiltration site. The concentration of these receptors is higher at the labral base and the central round ligament (along with vascular structures). In addition, they occur diffusely, in moderate concentrations, at the joint capsule.[16]
[17]
There are many analgesia modalities for the postoperative period of THA, including epidural analgesia, opioid administration, and peripheral nerve blocks. Although widely used, each technique has local and systemic side effects: epidural analgesia may result in pruritus and spinal cord ischemia; opioids can cause nausea, emetic episodes, respiratory depression, and urinary retention; and peripheral blocks may lead to neurovascular injury. In addition, a greater intensity of joint pain on the date of surgery is a risk factor for chronic opioid use. Among THA patients, 4.3% of those who had never used opioids before and 34.7% of those who used them continued to take them 6 months after surgery.[18]
Methodology
This is a primary, experimental, quantitative (analytical), randomized double-blind controlled clinical study in patients with femoral neck fracture or hip osteoarthrosis who underwent a total hip arthroplasty at our institution. This study used the non-probabilistic convenience sampling method. A software-based permuted randomization process assigned patients to their groups. The exclusion criteria were scheduled surgical reintervention procedures in a previously operated hip and impossibility to undergo spinal anesthesia.
Selected patients underwent spinal anesthesia. The experimental group received a postoperative periarticular infiltration with levobupivacaine (0.75% concentration, 20 mL volume) and dexamethasone (4 mg/mL, 2.5 mL vial, totaling 10 mg) diluted in a saline solution (in a total volume of approximately 60 mL). This solution was applied after implant placement in the remaining hip joint capsule (postcapsulorrhaphy), the external rotators (after suturing them), the periarticular gluteal musculature, and the periosteum adjacent to the implants. The control group (placebo) received an infiltration of the same volume of 0.9% saline solution in the same tissues ([Figure 1]).
Fig. 1 Infiltration sites at the hip after prosthesis placement—joint capsule and external rotators (white arrows), periarticular gluteal muscles (yellow arrows), and periosteum adjacent to the femoral and acetabular implants (blue arrows).
Results
This study included 35 patients diagnosed with femoral neck fracture or hip osteoarthritis from October 2018 to December 2020 who underwent total hip arthroplasty. One patient developed hemodynamic complications and was excluded from the study because the assessment was not possible.
The evaluation included pain (visual analog scale [VAS]), hip range of motion, analgesic agent intake, length of hospitalization, ability to walk, and postoperative complications.
Data analysis used the statistical software Statistica version 7.0 (StatSoft, Tulsa, OK, USA). The established significance level was 5%.
The patients ages ranged from 44 to 82 years old, with a mean age of 64.15. There was no statistically significant difference between groups regarding age (p = 0.29).
There was no statistically significant difference between groups regarding surgical indication (p = 0.45). The main indication for both groups was coxarthrosis ([Table 1]).
Table 1
|
Group
|
|
Indication
|
Placebo
|
Experimental
|
Total
|
Coxarthrosis
|
11
|
13
|
24
|
%
|
64.71%
|
76.47%
|
|
Neck fracture
|
6
|
4
|
10
|
%
|
35.29%
|
23.53%
|
|
Total
|
17
|
17
|
34
|
The experimental group presented a significant change in opioids intake between 24 and 48 hours. A significant number of patients no longer needed opioids after 48 hours ([Table 2]).
Table 2
Placebo
|
48 hours
|
|
Experimental
|
48 hours
|
|
24 hours
|
No
|
Yes
|
Total
|
24 hours
|
No
|
Yes
|
Total
|
No
|
5
|
0
|
5
|
No
|
6
|
0
|
6
|
%
|
62.50%
|
0.00%
|
|
%
|
50.00%
|
0.00%
|
|
Yes
|
3
|
9
|
12
|
Yes
|
6
|
5
|
11
|
%
|
37.50%
|
100.00%
|
|
%
|
50.00%
|
100.00%
|
|
Total
|
8
|
9
|
17
|
Total
|
12
|
5
|
17
|
P
|
0.0248
|
|
P
|
0.041
|
|
The placebo group showed no significant change between the 24- and 48-hour period ([Table 3]).
Table 3
Group
|
Mean
|
n
|
Standard deviation
|
Minimum value
|
Maximum value
|
Placebo
|
−2.80
|
15
|
1.93
|
−6
|
1
|
Experimental
|
−1.35
|
17
|
1.22
|
−3
|
2
|
Total
|
−2.03
|
32
|
1.73
|
−6
|
2
|
There was a significant difference between the groups regarding pain (p = 0.033). The placebo group presented a greater reduction in pain scores when comparing patients at 24 and 48 hours.
There was no significant difference between groups regarding range of motion, including flexion (p = 0.81), adduction (p = 0.84), abduction (p = 0.61), internal (p = 0.18) or external rotation (p = 0.54).
There was also no statistically significant difference between groups regarding time to resume walking (p = 0.68), length of hospitalization (p = 0.45), or postoperative complications (p = 0.24).
Discussion
There is little standardization regarding the therapeutic regimens for periarticular infiltration in the literature. Multiple studies have compared different drug combinations but with no precise definition of the ideal mixture. The analysis of the pharmacology of these agents should help the optimal choice and allow surgeons to use what they prefer.[19]
Infiltration in the soft tissues around the hip joint, including the joint capsule, direct and reflex heads of the rectus femoris, tensor fascia lata, and subcutaneous tissue, shows good results in postoperative analgesia.[20] The literature also describes infiltration in external rotators and gluteus, as well as the posterior capsule and gluteus medius attachment site, but with no satisfactory outcomes.[21]
In this study, although there was a higher temporal reduction (from 24–48 hours) of pain scores in the placebo group (compared to the experimental group), opioid intake decreased significantly only in the experimental group between 24 and 48 hours.
There were no differences in hip mobility between groups, including the range of motion in all analyzed planes. The length of hospitalization, early mobility (beginning to walk), or complication rates presented no significant differences.
Conclusion
Periarticular anesthetic infiltration as a method of postoperative analgesia for total hip arthroplasty reduced the rates of opioid intake from 24 to 48 hours. There were no benefits regarding pain, mobility, length of stay, or complications with this method.